cmd: mdc/mwc: normalize disjoint MX_CYCLIC usage

Both CMD_MX_CYCLIC and MX_CYCLIC are in use and defined in Kconfig,
but only the non-CMD version currently does anything. This changes all
usages to prefer the CMD_MX_CYCLIC option (since it's only affecting
addition of the commands), and switches defconfigs using the non-CMD
version to use the CMD version.

Signed-off-by: Joel Johnson <mrjoel@lixil.net>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/k2l_hs_evm_defconfig b/configs/k2l_hs_evm_defconfig
index d7210df..3fad15f 100644
--- a/configs/k2l_hs_evm_defconfig
+++ b/configs/k2l_hs_evm_defconfig
@@ -16,7 +16,7 @@
 CONFIG_VERSION_VARIABLE=y
 CONFIG_BOARD_EARLY_INIT_F=y
 CONFIG_HUSH_PARSER=y
-CONFIG_MX_CYCLIC=y
+CONFIG_CMD_MX_CYCLIC=y
 # CONFIG_CMD_FLASH is not set
 # CONFIG_CMD_GPIO is not set
 # CONFIG_CMD_GPT is not set