MIPS: Au1x00: Move all Au1x00 specific code to separate subdirectory

Au1x00 is a SoC and its specific code should reside in an own
SoC subdirectory. Also add -mtune=4kc flag for CPU optimization.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Cc: Thomas Lange <thomas@corelatus.se>
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
diff --git a/boards.cfg b/boards.cfg
index 7844bbd..9a8dbb3 100644
--- a/boards.cfg
+++ b/boards.cfg
@@ -217,17 +217,17 @@
 M53017EVB                    m68k        mcf52x2     m53017evb           freescale
 EP2500                       m68k        mcf52x2     ep2500              Mercury
 microblaze-generic           microblaze  microblaze  microblaze-generic  xilinx
-dbau1000                     mips        mips32      dbau1x00            -              -           dbau1x00:DBAU1000
-dbau1100                     mips        mips32      dbau1x00            -              -           dbau1x00:DBAU1100
-dbau1500                     mips        mips32      dbau1x00            -              -           dbau1x00:DBAU1500
-dbau1550                     mips        mips32      dbau1x00            -              -           dbau1x00:DBAU1550
-dbau1550_el                  mips        mips32      dbau1x00            -              -           dbau1x00:DBAU1550
-gth2                         mips        mips32
+dbau1000                     mips        mips32      dbau1x00            -              au1x00      dbau1x00:DBAU1000
+dbau1100                     mips        mips32      dbau1x00            -              au1x00      dbau1x00:DBAU1100
+dbau1500                     mips        mips32      dbau1x00            -              au1x00      dbau1x00:DBAU1500
+dbau1550                     mips        mips32      dbau1x00            -              au1x00      dbau1x00:DBAU1550
+dbau1550_el                  mips        mips32      dbau1x00            -              au1x00      dbau1x00:DBAU1550
+gth2                         mips        mips32      -                   -              au1x00
 incaip                       mips        mips32      incaip              -              incaip
 incaip_100MHz                mips        mips32      incaip              -              incaip      incaip:CPU_CLOCK_RATE=100000000
 incaip_133MHz                mips        mips32      incaip              -              incaip      incaip:CPU_CLOCK_RATE=133000000
 incaip_150MHz                mips        mips32      incaip              -              incaip      incaip:CPU_CLOCK_RATE=150000000
-pb1000                       mips        mips32      pb1x00              -              -           pb1x00:PB1000
+pb1000                       mips        mips32      pb1x00              -              au1x00      pb1x00:PB1000
 qemu_mips                    mips        mips32      qemu-mips           -              -           qemu-mips
 tb0229                       mips        mips32
 vct_premium                  mips        mips32      vct                 micronas       -           vct:VCT_PREMIUM