openssl: fix m68k uclinux compile

The GCC manual suggest when getting:
relocation truncated to fit: R_68K_GOT16O foobar
to use -mxgot.

Fixes:
http://autobuild.buildroot.net/results/455fd0f274bfa4bbd786bcd6740ecf960e47c1bd/

Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/openssl/openssl.mk

@@ -19,6 +19,11 @@ OPENSSL_PATCH = \
 	https://gitweb.gentoo.org/repo/gentoo.git/plain/dev-libs/openssl/files/openssl-1.0.2a-parallel-install-dirs.patch?id=c8abcbe8de5d3b6cdd68c162f398c011ff6e2d9d \
 	https://gitweb.gentoo.org/repo/gentoo.git/plain/dev-libs/openssl/files/openssl-1.0.2a-parallel-symlinking.patch?id=c8abcbe8de5d3b6cdd68c162f398c011ff6e2d9d
 
+# relocation truncated to fit: R_68K_GOT16O
+ifeq ($(BR2_m68k_cf),y)
+OPENSSL_CFLAGS += -mxgot
+endif
+
 ifeq ($(BR2_USE_MMU),)
 OPENSSL_CFLAGS += -DHAVE_FORK=0
 endif