arm:mmc only compile mmchs when targeting arm.

Change-Id: Ie8d0b6461b58c2a7becda98401dece81be607a01

drivers/mmc/Makefile

@@ -1,6 +1,12 @@
 # Makefile for the mmc driver.
 PROG=	mmc
-SRCS=	mmcblk.c mmchost_mmchs.c mmchost_dummy.c mmclog.h sdhcreg.h sdmmcreg.h
+SRCS=	mmcblk.c mmchost_dummy.c mmclog.h sdhcreg.h sdmmcreg.h
+
+
+.if ${MACHINE_ARCH} == "earm"
+SRCS += mmchost_mmchs.c 
+.endif
+
 
 DPADD+=	${LIBBLOCKDRIVER} ${LIBSYS}
 LDADD+=	-lblockdriver -lsys

drivers/mmc/mmcblk.c

@@ -112,7 +112,9 @@ apply_env()
 	    || strncmp(driver, "mmchs", strlen("mmchs") + 1) == 0) {
 		/* early init of host mmc host controller. This code should
 		 * depend on knowing the hardware that is running bellow. */
+#ifdef __arm__
 		host_initialize_host_structure_mmchs(&host);
+#endif
 	} else if (strncmp(driver, "dummy", strlen("dummy") + 1) == 0) {
 		host_initialize_host_structure_dummy(&host);
 	} else {