[golan] Fix build error on some versions of gcc

Some versions of gcc complain that "'__bswap_variable_32' is static
but used in inline function 'golan_check_rc_and_cmd_status' which is
not static".

Fix by making golan_check_rc_and_cmd_status() a static inline.

Modified-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/drivers/infiniband/golan.c

 	"ERR"
 };
 
-inline int golan_check_rc_and_cmd_status ( struct golan_cmd_layout *cmd, int rc ) {
+static inline int golan_check_rc_and_cmd_status ( struct golan_cmd_layout *cmd, int rc ) {
 	struct golan_outbox_hdr *out_hdr = ( struct golan_outbox_hdr * ) ( cmd->out );
 	if ( rc == -EBUSY ) {
 		DBG ( "HCA is busy (rc = -EBUSY)\n" );