toolchain/uClibc: Disable mips16 for uClibc for now

toolchain/uClibc: Disable mips16 for uClibc for now

For now, build uclibc without -mips16. There's no mips16 syscall
support AFAIK and uclibc uses inline assembly syscalls a lot.

In addition, touching errno means touching a TLS model symbol, and
that's not supported in gcc 4.6.

The __set_errno macro can be put back to calling
errno_location(). This allows much of the library to be built in
mips16 mode. I don't understand the implications to the thread library
of doing this.

A list of "build as -mno-mips16" C source files can be placed in the
mips architecture-dependent build files. Maintaining the list would be
no fun.

Signed-off-by: Jay Carlson <nop@nop.com>
Signed-off-by: Florian Fainelli <florian@openwrt.org>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@36199 3c298f89-4303-0410-b956-a3cf2f4a3e73