8149479: Fix compare.sh to have a clean baseline with COMPARE_BUILD
Reviewed-by: ihse, tbell
os_family = solaris
arch = x86
arch_model = x86_64
os_arch = solaris_x86
os_arch_model = solaris_x86_64
lib_arch = amd64
compiler = sparcWorks
sysdefs = -DSOLARIS -DSPARC_WORKS -DAMD64