arm: mach-k3: Rename SOC_K3_AM6 to SOC_K3_AM654

The first AM6x device was the AM654x, but being the first we named it
just AM6, since more devices have come out with this same prefix we
should switch it to the normal convention of using the full name of the
first compatibility device the series. This makes what device we are
talking about more clear and matches all the K3 devices added since.

Signed-off-by: Andrew Davis <afd@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/ram/Kconfig b/drivers/ram/Kconfig
index 7c34618..86857c0 100644
--- a/drivers/ram/Kconfig
+++ b/drivers/ram/Kconfig
@@ -45,7 +45,7 @@
 
 config K3_AM654_DDRSS
 	bool "Enable AM654 DDRSS support"
-	depends on RAM && SOC_K3_AM6
+	depends on RAM && SOC_K3_AM654
 	help
 	  K3 based AM654 devices has DDR memory subsystem that comprises
 	  Synopys DDR controller, Synopsis DDR phy and wrapper logic to