elements/bootstrap/binutils.bst: Do not strip the linker

Otherwise programs like valgrind will not work with error messages like:
"
==3== Memcheck, a memory error detector
==3== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==3== Using Valgrind-3.14.0 and LibVEX; rerun with -h for copyright info
==3== Command: /app/bin/flatterm
==3==

valgrind:  Fatal error at startup: a function redirection
valgrind:  which is mandatory for this platform-tool combination
valgrind:  cannot be set up.  Details of the redirection are:
valgrind:
valgrind:  A must-be-redirected function
valgrind:  whose name matches the pattern:      strlen
valgrind:  in an object with soname matching:   ld-linux-x86-64.so.2
valgrind:  was not found whilst processing
valgrind:  symbols from the object with soname: ld-linux-x86-64.so.2
valgrind:
valgrind:  Possible fixes: (1, short term): install glibc's debuginfo
valgrind:  package on this machine.  (2, longer term): ask the packagers
valgrind:  for your Linux distribution to please in future ship a non-
valgrind:  stripped ld.so (or whatever the dynamic linker .so is called)
valgrind:  that exports the above-named function using the standard
valgrind:  calling conventions for this platform.  The package you need
valgrind:  to install for fix (1) is called
valgrind:
valgrind:    On Debian, Ubuntu:                 libc6-dbg
valgrind:    On SuSE, openSuSE, Fedora, RHEL:   glibc-debuginfo
valgrind:
valgrind:  Note that if you are debugging a 32 bit process on a
valgrind:  64 bit system, you will need a corresponding 32 bit debuginfo
valgrind:  package (e.g. libc6-dbg:i386).
valgrind:
valgrind:  Cannot continue -- exiting now.  Sorry.
"
8 jobs for jjardon/no_strip_ld in 17 minutes and 2 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Flatpak
failed #202127893
aarch64
app_aarch64

00:16:14

failed #202127894
armhf
app_arm

00:09:01

failed #202127891
cache_i686 x86_64
app_i686

00:17:02

failed #202127886
cache_x86_64 x86_64
app_x86_64

00:15:17

 
  Vm
skipped #202127901
aarch64 allowed to fail manual
minimal_systemd_vm_aarch64
skipped #202127902
armhf
minimal_systemd_vm_arm
skipped #202127899
cache_i686 x86_64
minimal_systemd_vm_i686
skipped #202127896
cache_x86_64 x86_64
minimal_systemd_vm_x86_64
 
Name Stage Failure
failed
app_i686 Flatpak
  Build Queue: processed 0,   skipped 29,  failed 0 
Push Queue: processed 0, skipped 29, failed 0


make: *** [Makefile:36: build] Error 255
Uploading artifacts...
/builds/freedesktop-sdk/freedesktop-sdk/cache/buildstream/logs: found 1360 matching files
Uploading artifacts to coordinator... ok
id=202127891 responseStatus=201 Created token=JKT_eTwH
ERROR: Job failed: exit code 1
failed
app_aarch64 Flatpak
  Build Queue: processed 0,   skipped 30,  failed 0 
Push Queue: processed 0, skipped 30, failed 0


make: *** [Makefile:36: build] Error 255
Uploading artifacts...
/builds/freedesktop-sdk/freedesktop-sdk/cache/buildstream/logs: found 1354 matching files
Uploading artifacts to coordinator... ok
id=202127893 responseStatus=201 Created token=Gng3dhsj
ERROR: Job failed: exit code 1
failed
app_x86_64 Flatpak
  Build Queue: processed 0,   skipped 27,  failed 0 
Push Queue: processed 11, skipped 16, failed 0


make: *** [Makefile:36: build] Error 255
Uploading artifacts...
/builds/freedesktop-sdk/freedesktop-sdk/cache/buildstream/logs: found 1259 matching files
Uploading artifacts to coordinator... ok
id=202127886 responseStatus=201 Created token=k43H7WkV
ERROR: Job failed: exit code 1
failed
app_arm Flatpak
  Build Queue: processed 0,   skipped 28,  failed 0  
Push Queue: processed 0, skipped 28, failed 0


make: *** [Makefile:36: build] Error 255
Uploading artifacts...
/builds/freedesktop-sdk/freedesktop-sdk/cache/buildstream/logs: found 1243 matching files
Uploading artifacts to coordinator... ok
id=202127894 responseStatus=201 Created token=1tX3aVpw
ERROR: Job failed: exit code 1