Changes to support big endian targets:

Changes to support big endian targets:

* src/ports.h
* src/SDCCglue.c
* src/avr/main.c
* src/ds390/main.c
* src/izt/i186.c
* src/mcs51/main.c
* src/pic/main.c
* src/pic16/main.c
* src/xa51/main.c
* src/z80/main.c

git-svn-id: https://sdcc.svn.sourceforge.net/svnroot/sdcc/trunk/sdcc@2819 4a8a32a2-be11-0410-ad9d-d568d2c75423