1.Add Targets/Bonito2g5536 directory
2.Add zloader.2g5536 directory
3.Add Makefile.2g5536 file
4.Add usb and ps2 keyboard functions
5.Modify 2g5536 codes to support gcc4.4
6.Modify gmac code in sys/dev/gmac for net device
Change-Id: I73c343fb4b08a50cb515cd7cbefaf624b6065498
Target:2G5536