warning removal changes

[Joel Sherrill]

Hi,

I have made numerous hopefully safe changes to eliminate
warnings over the past few days. My goal was to significantly
reduce the number of warnings on 16-bit targets but since
all the code in question was target independent, it impacted
other targets.  I eliminated over 1000 warnings for h8300/multilib
and about 1/2 for sparc/erc32. 

Please update your tree and test.  If you see problems or
have fixes for other warnings, please help.

We are primarily dealing with 16/32 bit integer issues and
pointer mangling that gcc doesn't like.  I would like to
be warning free. :)

Thanks.

--joel