RFR (XS): 8144881: Various fixes to linux/sparc

[Gerald Thornbrugh]

Hi Mikael,

I have one small nit, it looks like you need to update the copyright year in "src/cpu/sparc/vm/nativeInst_sparc.cpp”.

Other than that everything looks good.

Jerry
> On Dec 7, 2015, at 2:53 PM, Mikael Vidstedt <mikael.vidstedt at oracle.com> wrote:
> 
> 
> Please review this small change which fixes a handful of places which currently lead to build failures on linux/sparc. The changes are all relatively straightforward and come in a few different flavors:
> 
> * Incorrect format specifiers
> * "reaches end of function returning value"
> * wrong type name (sigcontext_t -> struct sigcontext)
> * wrong variable name (addr -> pc)
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8144881
> Webrev: http://cr.openjdk.java.net/~mikael/webrevs/8144881/webrev.00/webrev/
> 
> Cheers,
> Mikael
>