Convert CONFIG_MCFTMR to Kconfig

This converts the following to Kconfig:
   CONFIG_MCFTMR

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/cobra5272_defconfig b/configs/cobra5272_defconfig
index 3966121..096c640 100644
--- a/configs/cobra5272_defconfig
+++ b/configs/cobra5272_defconfig
@@ -5,6 +5,7 @@
 CONFIG_ENV_SECT_SIZE=0x2000
 CONFIG_DEFAULT_DEVICE_TREE="cobra5272"
 CONFIG_TARGET_COBRA5272=y
+CONFIG_MCFTMR=y
 CONFIG_SYS_LOAD_ADDR=0x20000
 CONFIG_BOOTDELAY=5
 # CONFIG_DISPLAY_BOARDINFO is not set