soc: nxp_rw6xx: Add support for XTAL32K clock

This clock is used for certain peripherals such
as RTC.
On certain RW612 boards such as rd_rw612_bga, XTAL32K
and ENET share pins. Add code to check if ENET and
XTAL32 are enabled at the same time.

Signed-off-by: Mahesh Mahadevan <mahesh.mahadevan@nxp.com>

soc/nxp/rw/Kconfig

@@ -55,4 +55,9 @@ endif # NXP_RW6XX_BOOT_HEADER
 rsource "../common/Kconfig.flexspi_xip"
 rsource "../common/Kconfig.nbu"
 
+config XTAL32K
+	bool "Use the External 32K clock"
+	help
+	  This clock is used by certain peripherals such as RTC.
+
 endif # SOC_SERIES_RW6XX

soc/nxp/rw/soc.c

@@ -201,6 +201,10 @@ __weak __ramfunc void clock_init(void)
 #if (DT_NODE_HAS_COMPAT_STATUS(DT_NODELABEL(flexcomm14), nxp_lpc_i2c, okay)) && CONFIG_I2C
 	CLOCK_AttachClk(kSFRO_to_FLEXCOMM14);
 #endif
+#if CONFIG_XTAL32K
+	CLOCK_EnableXtal32K(true);
+	CLOCK_AttachClk(kXTAL32K_to_CLK32K);
+#endif
 
 /* Clock flexcomms when used as SPI */
 #ifdef CONFIG_SPI