remoteproc: imx: Broaden the Kconfig selection logic

Besides i.MX6SX and i.MX7D, there are other i.MX devices that contain
Cortex M4 and could make use of the imx remoteproc driver, such as
i.MX7ULP, i.MX8M, etc.

Instead of adding new SoC entries in the Kconfig logic, make it
broader by using the more generic ARCH_MXC, which encompasses
all the 32-bit and 64-bit i.MX devices.
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

drivers/remoteproc/Kconfig

@@ -15,7 +15,7 @@ if REMOTEPROC
 
 config IMX_REMOTEPROC
 	tristate "IMX6/7 remoteproc support"
-	depends on SOC_IMX6SX || SOC_IMX7D
+	depends on ARCH_MXC
 	help
 	  Say y here to support iMX's remote processors (Cortex M4
 	  on iMX7D) via the remote processor framework.