meson: .gitlab-ci.yml: switch armv7l build to Debian 10

On Debian Sid there are broken headers for cross compilation. There is
no <asm/kvm.h> header unconditionally included by <linux/kvm.h>.

With autotools the build works correctly because the header detection
tries to compile simple code that includes the header but with Meson
the detection works differently. We check <linux/kvm.h> which is present
so it should be safe to include it.

We could workaround it in libvirt by checking for presence of
<asm/kvm.h> as well but I don't believe that's a correct approach.
IMHO it should be fixed in Debian.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>

.gitlab-ci.yml

@@ -364,6 +364,12 @@ armv6l-debian-10:
     NAME: debian-10
     CROSS: armv6l
 
+armv7l-debian-10:
+  <<: *cross_build_job_definition
+  variables:
+    NAME: debian-10
+    CROSS: armv7l
+
 mips64el-debian-10:
   <<: *cross_build_job_definition
   variables:
@@ -394,12 +400,6 @@ s390x-debian-sid:
     NAME: debian-sid
     CROSS: s390x
 
-armv7l-debian-sid:
-  <<: *cross_build_job_definition
-  variables:
-    NAME: debian-sid
-    CROSS: armv7l
-
 i686-debian-sid:
   <<: *cross_build_job_definition
   variables: