include: env: ti: mmc: envboot/mmcboot: Check result of mmc dev before proceeding

If mmc dev reports that the device is not present, there is no point in
proceeding further to attempt to load the files.

Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
diff --git a/include/env/ti/mmc.env b/include/env/ti/mmc.env
index 6fb47fb..b8eb51c 100644
--- a/include/env/ti/mmc.env
+++ b/include/env/ti/mmc.env
@@ -15,7 +15,7 @@
 loadimage=load ${devtype} ${bootpart} ${loadaddr} ${bootdir}/${bootfile}
 loadfdt=load ${devtype} ${bootpart} ${fdtaddr} ${bootdir}/dtb/${fdtfile}
 get_fdt_mmc=load mmc ${bootpart} ${fdtaddr} ${bootdir}/dtb/${name_fdt}
-envboot=mmc dev ${mmcdev};
+envboot=if mmc dev ${mmcdev}; then
 	if mmc rescan; then
 		echo SD/MMC found on device ${mmcdev};
 		if run loadbootscript; then
@@ -31,6 +31,7 @@
 			fi;
 		fi;
 	fi;
+  fi;
 mmcloados=
 	if test ${boot_fdt} = yes || test ${boot_fdt} = try; then
 		if run get_fdt_mmc; then
@@ -45,7 +46,7 @@
 	else
 		bootz;
 	fi;
-mmcboot=mmc dev ${mmcdev};
+mmcboot=if mmc dev ${mmcdev}; then
 	devnum=${mmcdev};
 	devtype=mmc;
 	if mmc rescan; then
@@ -58,7 +59,8 @@
 				run mmcloados;
 			fi;
 		fi;
-fi;
+	fi;
+  fi;
 
 init_mmc=run args_all args_mmc
 get_overlay_mmc=