[committed] Use $15 as the MIPS static chain register.

[Richard Sandiford]

Richard Sandiford <rdsandiford@googlemail.com> writes:
> Only the MIPS SDE MDK configuration supports MIPS16 profiling, and it
> doesn't support PIC, so neither of the patched FUNCTION_PROFILERs
> will clobber the static chain register.

Err, I meant: neither of the patched FUNCTION_PROFILERs
will clobber a $2 GP value.

Richard