MIPS: fix endianess handling

Make endianess of target CPU configurable. Use the new config
option for dbau1550_el and pb1000 boards.

Adapt linking of standalone applications to pass through
endianess options to LD.

Build tested with:
 - ELDK 4 mips_4KC- and mips4KCle
 - Sourcery CodeBench Lite 2011.03-93

With this patch all 26 MIPS boards can be compiled now in one step by
running "MAKEALL -a mips".

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
diff --git a/boards.cfg b/boards.cfg
index c6090ba..3cf75c3 100644
--- a/boards.cfg
+++ b/boards.cfg
@@ -360,7 +360,7 @@
 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
+dbau1550_el                  mips        mips32      dbau1x00            -              au1x00      dbau1x00:DBAU1550,SYS_LITTLE_ENDIAN
 gth2                         mips        mips32      -                   -              au1x00
 pb1000                       mips        mips32      pb1x00              -              au1x00      pb1x00:PB1000
 incaip                       mips        mips32      incaip              -              incaip