MIPS: Fix delay slot emulation count in debugfs

MIPS: Fix delay slot emulation count in debugfs

Commit 26dd3bd5cfcc ("MIPS: Use per-mm page to execute branch delay slot
instructions") accidentally removed use of the MIPS_FPU_EMU_INC_STATS
macro from do_dsemulret, leading to the ds_emul file in debugfs always
returning zero even though we perform delay slot emulations.

Fix this by re-adding the use of the MIPS_FPU_EMU_INC_STATS macro.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 26dd3bd5cfcc ("MIPS: Use per-mm page to execute branch delay slot instructions")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14301/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>