Pull MIPS fixes from Paul Burton:
- Build fixes for CONFIG_OPTIMIZE_INLINING=y builds in which the
compiler may choose not to inline __xchg() & __cmpxchg().
- A build fix for Loongson configurations with GCC 9.x.
- Expose some extra HWCAP bits to indicate support for various
instruction set extensions to userland.
- Fix bad stack access in firmware handling code for old SNI
RM200/300/400 machines.
* tag 'mips_fixes_5.4_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: Disable Loongson MMI instructions for kernel build
MIPS: elf_hwcap: Export userspace ASEs
MIPS: fw: sni: Fix out of bounds init of o32 stack
MIPS: include: Mark __xchg as __always_inline
MIPS: include: Mark __cmpxchg as __always_inline