arm: mach-k3: Move R5 specific code into new r5/ directory

This makes it clear these are only to be used by the R5 builds of SPL.
And this will be used to later more cleanly split the two builds.

Signed-off-by: Andrew Davis <afd@ti.com>
diff --git a/arch/arm/mach-k3/Makefile b/arch/arm/mach-k3/Makefile
index c7ca0fd..215c755 100644
--- a/arch/arm/mach-k3/Makefile
+++ b/arch/arm/mach-k3/Makefile
@@ -3,12 +3,8 @@
 # Copyright (C) 2017-2018 Texas Instruments Incorporated - https://www.ti.com/
 #	Lokesh Vutla <lokeshvutla@ti.com>
 
-obj-$(CONFIG_SOC_K3_J721E) += j721e/ j7200/
-obj-$(CONFIG_SOC_K3_J721S2) += j721s2/
-obj-$(CONFIG_SOC_K3_AM625) += am62x/
-obj-$(CONFIG_SOC_K3_AM62A7) += am62ax/
+obj-$(CONFIG_CPU_V7R) += r5/
 obj-$(CONFIG_ARM64) += arm64-mmu.o
-obj-$(CONFIG_CPU_V7R) += r5_mpu.o lowlevel_init.o
 obj-$(CONFIG_ARM64) += cache.o
 obj-$(CONFIG_OF_LIBFDT) += common_fdt.o
 ifeq ($(CONFIG_OF_LIBFDT)$(CONFIG_OF_SYSTEM_SETUP),yy)