nss: Build on mips64

Now that we have mips64 qemu support in OE-Core
this started to fail to build. So lets fix it

Signed-off-by: Khem Raj <raj.khem@gmail.com>
CC: Eric Bénard <eric@eukrea.com>
CC: Denis Carikli <denis@eukrea.com>
CC: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Eric Bénard <eric@eukrea.com>