build: fix autotools configure bashisms
'==' is a Bashism and will fail when ./configure is run with /bin/sh provided by a POSIX-compliant shell.
Bug: https://bugs.gentoo.org/829494 Signed-off-by: Sam James sam@gentoo.org
'==' is a Bashism and will fail when ./configure is run with /bin/sh provided by a POSIX-compliant shell.
Bug: https://bugs.gentoo.org/829494 Signed-off-by: Sam James sam@gentoo.org