Kconfigs: Correct default of "0" on hex type entries

It is not a parse error to have a default value of "0" for a "hex" type
entry, instead of "0x0".  However, "0" and "0x0" are not treated the
same even by the tools themselves. Correct this by changing the default
value from "0" to "0x0" for all hex type questions that had the
incorrect default. Fix one instance (in two configs) of a default of "0"
being used on a hex question to be "0x0". Remove the cases where a
defconfig had set a value of "0x0" to be used as the default had been
"0".

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

drivers/i2c/Kconfig

@@ -372,7 +372,7 @@ config SYS_MXC_I2C1_SPEED
 
 config SYS_MXC_I2C1_SLAVE
 	hex "I2C1 Slave"
-	default 0
+	default 0x0
 	help
 	 MXC I2C1 Slave
 endif
@@ -387,7 +387,7 @@ config SYS_MXC_I2C2_SPEED
 
 config SYS_MXC_I2C2_SLAVE
 	hex "I2C2 Slave"
-	default 0
+	default 0x0
 	help
 	 MXC I2C2 Slave
 endif
@@ -401,7 +401,7 @@ config SYS_MXC_I2C3_SPEED
 
 config SYS_MXC_I2C3_SLAVE
 	hex "I2C3 Slave"
-	default 0
+	default 0x0
 	help
 	 MXC I2C3 Slave
 endif
@@ -415,7 +415,7 @@ config SYS_MXC_I2C4_SPEED
 
 config SYS_MXC_I2C4_SLAVE
 	hex "I2C4 Slave"
-	default 0
+	default 0x0
 	help
 	 MXC I2C4 Slave
 endif
@@ -429,7 +429,7 @@ config SYS_MXC_I2C5_SPEED
 
 config SYS_MXC_I2C5_SLAVE
 	hex "I2C5 Slave"
-	default 0
+	default 0x0
 	help
 	 MXC I2C5 Slave
 endif
@@ -443,7 +443,7 @@ config SYS_MXC_I2C6_SPEED
 
 config SYS_MXC_I2C6_SLAVE
 	hex "I2C6 Slave"
-	default 0
+	default 0x0
 	help
 	 MXC I2C6 Slave
 endif
@@ -457,7 +457,7 @@ config SYS_MXC_I2C7_SPEED
 
 config SYS_MXC_I2C7_SLAVE
 	hex "I2C7 Slave"
-	default 0
+	default 0x0
 	help
 	 MXC I2C7 Slave
 endif
@@ -471,7 +471,7 @@ config SYS_MXC_I2C8_SPEED
 
 config SYS_MXC_I2C8_SLAVE
 	hex "I2C8 Slave"
-	default 0
+	default 0x0
 	help
 	 MXC I2C8 Slave
 endif