[MIPS] TXx9: Reorganize code

Move arch/mips/{jmr3927,tx4927,tx4938} into arch/mips/txx9/ tree.
This will help more code sharing and maintainance.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/txx9/rbtx4927/Makefile b/arch/mips/txx9/rbtx4927/Makefile
new file mode 100644
index 0000000..f3e1f59
--- /dev/null
+++ b/arch/mips/txx9/rbtx4927/Makefile
@@ -0,0 +1,3 @@
+obj-y	+= prom.o setup.o irq.o
+
+EXTRA_CFLAGS += -Werror