cadence_gem: initial version of device model

Device model for cadence gem ethernet controller.
Signed-off-by: NPeter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
Signed-off-by: NJohn Linn <john.linn@xilinx.com>
Acked-by: NEdgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: NEdgar E. Iglesias <edgar.iglesias@gmail.com>

Makefile.target

@@ -348,6 +348,7 @@ obj-arm-y += arm_boot.o pl011.o pl031.o pl050.o pl080.o pl110.o pl181.o pl190.o
 obj-arm-y += versatile_pci.o
 obj-arm-y += cadence_uart.o
 obj-arm-y += cadence_ttc.o
+obj-arm-y += cadence_gem.o
 obj-arm-y += realview_gic.o realview.o arm_sysctl.o arm11mpcore.o a9mpcore.o
 obj-arm-y += exynos4210_gic.o exynos4210_combiner.o exynos4210.o
 obj-arm-y += exynos4_boards.o exynos4210_uart.o exynos4210_pwm.o