configure: Disable arm movw/movt relocations for GCC

configure: Disable arm movw/movt relocations for GCC

When building for arm, we already disable movw/movt relocations for clang,
since they are incompatible with PE.

When building with bare metal GCC toolchains (like the one used in the
travis ci scripts), we end up with these relocations again. So add an
additional test for the '-mword-relocations' flag used by GCC.

Reported-by: Alexander Graf <agraf@csgraf.de>
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>