Draft: [Sprint] Compiling stdlib with LFortran

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cc: @certik I will push quick fixes to this MR for compiling stdlib with lfortran. Note that above versions of make and cmake should be used along with master-lfortran (I have updated it recently so please update your local version) branch in my fork to make this work.

Current progress,

[ 47%] Building Fortran object src/CMakeFiles/fortran_stdlib.dir/stdlib_strings_to_string.f90.o
[ 48%] Building Fortran object src/CMakeFiles/fortran_stdlib.dir/stdlib_system.F90.o
[ 49%] Linking Fortran static library libfortran_stdlib.a
warning: /Library/Developer/CommandLineTools/usr/bin/ranlib: archive library: libfortran_stdlib.a the table of contents is empty (no object file members in the library define global symbols)
[ 49%] Built target fortran_stdlib
Scanning dependencies of target test_always_skip
[ 50%] Building Fortran object src/tests/CMakeFiles/test_always_skip.dir/test_always_skip.f90.o
semantic error: Module 'stdlib_error' not declared in the current source and the modfile was not found
 --> /Users/czgdp1807/lfortran_project/stdlib/src/tests/test_always_skip.f90:3:1
  |
3 | use stdlib_error, only: check
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 


Note: if any of the above error or warning messages are not clear or are lacking
context please report it to us (we consider that a bug that needs to be fixed).
make[2]: *** [src/tests/CMakeFiles/test_always_skip.dir/build.make:75: src/tests/CMakeFiles/test_always_skip.dir/test_always_skip.f90.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:428: src/tests/CMakeFiles/test_always_skip.dir/all] Error 2
make: *** [Makefile:146: all] Error 2

Commits to be cherry-picked,

1. 65334a8c (!1729 (merged))
2. ea462156 (!1730 (merged))
3. 1db54062 (!1740 (merged))
4. 74912464 (!1729 (merged))
5. 0dd70d27 (!1731 (merged))
6. 21918732 (!1732 (merged))
7. 0395a0c3 (!1734 (merged))
8. 07883e70 (!1733 (merged))
9. ef70e92b (!1733 (merged), except count intrinsic)
10. d53bdf72 (!1733 (merged), !1734 (merged), !1747 (merged) for cmplx)
11. 000a7a22 (!1734 (merged) for dotproduct and merge, !1747 (merged) for cmplx, !1740 (merged))
12. f68fdd28
13. ab22afd0 (!1738 (merged), except ast_common_visitor.h changes)
14. f1e1d894
15. 93b9c399 (!1738 (merged))
16. a140cdbe (!1738 (merged) for ieee_is_nan, !1739 (merged) for pack)
17. c1e276a9 (!1735 (merged))
18. 7d6bbcce (!1746 (closed))
19. 56e69401 (!1738 (merged) for adjustr, !1746 (closed) for generic procedure fallback)
20. c9ab20a9
21. e20d54a8 (!1738 (merged))
22. 39cee398 (!1746 (closed))
23. eba12440 (!1739 (merged) for transfer, !1740 (merged))
24. e91cc2d5 (!1740 (merged))
25. 871a6dcc (!1732 (merged))
26. d05f1ab3 (!1738 (merged))