same70b: Add support for SMC for SAME70-series

[AsgeirSH]

The Static Memory Controller driver (which is already implemented for SAM4S in the existing memc) is not enabled for SAME70, nor does it support the 16-bit memory width of that SMC. This PR (with the accompanying one in hal_atmel) adds this support.

Tested on a custom board, and tests for SAM4S build locally (tests/drivers/memc/ram).

• Add smc definition in same70.dtsi.
• Add atmel,smc-bus-width to atmel,sam-smc dts bindings. Update driver to select bus width from DT.

[github-actions]

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[zephyrbot]

The following west manifest projects have been modified in this Pull Request:

Name	Old Revision	New Revision	Diff
hal_atmel	zephyrproject-rtos/hal_atmel@56d60eb (master)	zephyrproject-rtos/hal_atmel#41	zephyrproject-rtos/hal_atmel#41/files

Note: This message is automatically posted and updated by the Manifest GitHub Action.

[nandojve]

-#if defined(CONFIG_SOC_SERIES_SAME70) || defined(CONFIG_SOC_SERIES_SAMV71)
-	#define BUS_WIDTH(node_id) COND_CODE_1(DT_ENUM_IDX(node_id, atmel_smc_bus_width), \
-	(SMC_MODE_DBW_16_BIT), (SMC_MODE_DBW_8_BIT))
-#else
-	#define BUS_WIDTH(node_id) (0)
-#endif
+#define BUS_WIDTH(node_id) COND_CODE_1(DT_ENUM_IDX(node_id, atmel_smc_bus_width), \
+			    (SMC_MODE_DBW_16_BIT), (0))

[nandojve]

        Bus Width configuration for the External Bus Interface. The
        Static Memory Controller that is wired to the external device.
        SMC on SAMx7 supports 8/16-bit bus width and on SAM4 only
        8-bit data bus is supported.

        The default value is 8-bit data buses.