Only use new symbol versioning with new gcc.
Only use new symbol versioning with new gcc.

57c6d01b5179b76a9244d4970f66c7cc1f643bd2 changes to using new symbol
versioning, but doesn't take the compiler version into account.

Signed-off-by: Peter Jones <2e0a021e603479ff81838c00c3b770daca4e0214@redhat.com>

rhboot/efivar,rhinstaller/efivar,rhinstaller/efivar,rhboot/efivar