ARM: configs: at91: sama5: MCP16502 regulator as built-in

This regulator is needed by several SoC or external peripherals on
different boards, providing required power rails.  Make it built-in
to match usual use-cases.
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>

arch/arm/configs/sama5_defconfig

@@ -138,7 +138,7 @@ CONFIG_REGULATOR=y
 CONFIG_REGULATOR_FIXED_VOLTAGE=y
 CONFIG_REGULATOR_ACT8865=y
 CONFIG_REGULATOR_ACT8945A=y
-CONFIG_REGULATOR_MCP16502=m
+CONFIG_REGULATOR_MCP16502=y
 CONFIG_REGULATOR_PWM=m
 CONFIG_MEDIA_SUPPORT=y
 CONFIG_MEDIA_SUPPORT_FILTER=y