fastmodel: Don't try to "staticify" system libraries.

We want to insist that the fast model libraries are the static versions
so they don't have to be found on non-system paths at run time, but we
don't need or want to do the same for system libraries which are from
standard paths on the host system.

Split the set of libraries fast model adds to the build into ones that
come from fast model itself, and ones it needs which should be
provided by the system. The ones from fast model itself should still
go through staticify, but the system libraries should be passed to the
compiler generically so it can pick which version it wants.

Change-Id: I222c94f8117143b86377150e686a4af669a994fe
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/51627
Maintainer: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Yu-hsin Wang <yuhsingw@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/arch/arm/fastmodel/SConscript

@@ -123,17 +123,20 @@ lib_paths = (
 env.Append(LIBPATH=lib_paths)
 env.Append(RPATH=lib_paths)
 
-libs = (
+fm_libs = (
     'components',
     'pvbus',
     'armctmodel',
     'fmruntime',
     'IrisSupport',
+)
+env.Append(LIBS=list(staticify(env, lib) for lib in fm_libs))
+system_libs = (
     'atomic',
     'dl',
     'rt',
 )
-env.Append(LIBS=list(staticify(env, lib) for lib in libs))
+env.Append(LIBS=system_libs)
 
 
 class ProjectFileParser(Grammar):