Commit a6d4d622 fixes incompatibility issue of GNU binutils 2.36 and later. If I check the diff of the commit, there seems to be asumption that the issue is specific to Linux. But it also happens on FreeBSD if user installs GNU binutils from FreeBSD ports/packages collections and '/usr/local/bin' comes before '/usr/bin' in the value of PATH enviroment variable. So fix the issue also on FreeBSD with following way.
- Introduce new macro 'HasGnuAr'.
- Change Imake.tmpl so it defines 'ArCmd' as 'ArCmdBase cq' if 'HasGnuAr' is defined.
- Define 'HasGnuAr' in both FreeBSD.cf and linux.cf.
Since 'ar' command of FreeBSD base system simply ignores 'l' option, it also works fine even if GNU binutils isn't installed.