imx: Remove boolean parameter from wdog powerdown function

imx_set_wdog_powerdown() is always used to disable the power down
enable bit, so remove the boolean parameter of the function.

It is also a bit strange to write a boolean value into registers,
so this new version makes explicit that we are writing 0.

While at it, rename it to imx_wdog_disable_powerdown().

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
diff --git a/arch/arm/mach-imx/mx6/soc.c b/arch/arm/mach-imx/mx6/soc.c
index ad72c12..43cb581 100644
--- a/arch/arm/mach-imx/mx6/soc.c
+++ b/arch/arm/mach-imx/mx6/soc.c
@@ -436,7 +436,7 @@
 	if (is_mx6sl())
 		setbits_le32(&ccm->cscmr1, MXC_CCM_CSCMR1_PER_CLK_SEL_MASK);
 
-	imx_set_wdog_powerdown(false); /* Disable PDE bit of WMCR register */
+	imx_wdog_disable_powerdown(); /* Disable PDE bit of WMCR register */
 
 	if (is_mx6sx())
 		setbits_le32(&ccm->cscdr1, MXC_CCM_CSCDR1_UART_CLK_SEL);