ARC: [TB10x] Add support for TB10x platform

Infrastructure required to make the Linux kernel compile and boot on the
Abilis Systems TB10x series of SOCs based on ARC700 CPUs:
  - Kmake related files (Kconfig, Makefile, tb10x_defconfig)
  - TB10x platform initialisation

Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Pierrick Hascoet <pierrick.hascoet@abilis.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 34974e2..491ae79 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -77,6 +77,7 @@
 menu "ARC Platform/SoC/Board"
 
 source "arch/arc/plat-arcfpga/Kconfig"
+source "arch/arc/plat-tb10x/Kconfig"
 #New platform adds here
 
 endmenu