Merge remote-tracking branch 'upstream/master'

Conflicts:
  llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp
  llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
  llvm/lib/Target/RISCV/MCTargetDesc/RISCVMCTargetDesc.cpp
  llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
  llvm/test/MC/RISCV/fde-reloc.s