Mainline build problems

[Aaron Gray]

There are problems with :-

       print-rtl.c:395
       c-common.c:4099
       c-pretty-print.c:822
       dwarf2asm.c:56
       dwarf2out.c:...
It seems to be a unsigned issue to do with HOST_WIDE_INT_PRINT_HEX, 
HOST_WIDE_INT_PRINT_DOUBLE_HEX and friends.

Aaron