mfd: Fix menelaus mmc slot 2 misconfiguration

We are modifying register value instead of return value.

This fix is originally done by Carlos Eduardo Aguiar. Original fix is
commit bb4e91722e29efe31587d2cc664b6def645aecd9 in
git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6.git

Author modified the fix for mainline version of menelaus.

Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Cc: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/menelaus.c

@@ -356,9 +356,9 @@ int menelaus_set_mmc_slot(int slot, int enable, int power, int cd_en)
 		int b;
 
 		if (enable)
-			ret |= 1 << 1;
+			val |= 1 << 1;
 		else
-			ret &= ~(1 << 1);
+			val &= ~(1 << 1);
 		b = menelaus_read_reg(MENELAUS_MCT_CTRL2);
 		b &= ~0x03;
 		b |= power;