[RISCV][ELF] Add RISCV GNU property label

Author: SuHo-llrr

llvm/include/llvm/BinaryFormat/ELF.h

@@ -1667,6 +1667,7 @@ enum : unsigned {
   GNU_PROPERTY_NO_COPY_ON_PROTECTED = 2,
   GNU_PROPERTY_AARCH64_FEATURE_1_AND = 0xc0000000,
   GNU_PROPERTY_X86_FEATURE_1_AND = 0xc0000002,
+  GNU_PROPERTY_RISCV_FEATURE_1_AND = 0xc0000000,
 
   GNU_PROPERTY_X86_UINT32_OR_LO = 0xc0008000,
   GNU_PROPERTY_X86_FEATURE_2_NEEDED = GNU_PROPERTY_X86_UINT32_OR_LO + 1,
@@ -1705,6 +1706,12 @@ enum : unsigned {
   GNU_PROPERTY_X86_ISA_1_V4 = 1 << 3,
 };
 
+// riscv processor feature bits.
+enum : unsigned {
+  GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP = 1 << 0,
+  GNU_PROPERTY_RISCV_FEATURE_1_ZICFISS = 1 << 1,
+};
+
 // FreeBSD note types.
 enum {
   NT_FREEBSD_ABI_TAG = 1,