Pull nds32 updates from Greentime Hu:
- Perf support
- Power management support
- FPU support
- Hardware prefetcher support
- Build error fixed
- Performance enhancement
* tag 'nds32-for-linus-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux:
nds32: support hardware prefetcher
nds32: Fix the items of hwcap_str ordering issue.
math-emu/soft-fp.h: (_FP_ROUND_ZERO) cast 0 to void to fix warning
math-emu/op-2.h: Use statement expressions to prevent negative constant shift
nds32: support denormalized result through FP emulator
nds32: Support FP emulation
nds32: nds32 FPU port
nds32: Remove duplicated include from pm.c
nds32: Power management for nds32
nds32: Add document for NDS32 PMU.
nds32: Add perf call-graph support.
nds32: Perf porting
nds32: Fix bug in bitfield.h
nds32: Fix gcc 8.0 compiler option incompatible.
nds32: Fill all TLB entries with kernel image mapping
nds32: Remove the redundant assignment