Build failure on MIPS (strtorx.c)

[Steve Ellcey]

The recent changes to strtorx.c and strtodg.c seem to have broken the
MIPS newlib build.  My build is currently failing while compiling strtorx.c.
It complains that ldus_QNAN[01234] are undeclared and that the use of
_strtodg_r is an implicit function reference.

I am not sure what the correct fix for this is.  I see the definitions
of ldus_QNAN* in newlib/libc/stdlib/gd_qnan.h and that it is ifdef'ed
for MIPS.  It looks like if __mips is defined then none of the ldus_QNAN
macros are defined but I don't know if they should be defined or if the
uses of them in strtorx.c should be ifdef'ed out for MIPS.

Steve Ellcey
sellcey@imgtec.com