Store sysreg names in-line with their descriptors. (llvm#119157)

This wastes some disk space, because we have to size the arrays for
the maximum possible length. However, it eliminates dynamic relocations
from the SysRegsList arrays.

Author: resistor

llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.h

@@ -700,8 +700,8 @@ AArch64StringToVectorLayout(StringRef LayoutStr) {
 
 namespace AArch64SysReg {
   struct SysReg {
-    const char *Name;
-    const char *AltName;
+    const char Name[32];
+    const char AltName[32];
     unsigned Encoding;
     bool Readable;
     bool Writeable;

llvm/lib/Target/ARM/Utils/ARMBaseInfo.h

@@ -189,7 +189,7 @@ inline static unsigned ARMCondCodeFromString(StringRef CC) {
 // System Registers
 namespace ARMSysReg {
   struct MClassSysReg {
-    const char *Name;
+    const char Name[32];
     uint16_t M1Encoding12;
     uint16_t M2M3Encoding8;
     uint16_t Encoding;

llvm/lib/Target/RISCV/MCTargetDesc/RISCVBaseInfo.h

@@ -452,9 +452,9 @@ int getLoadFPImm(APFloat FPImm);
 
 namespace RISCVSysReg {
 struct SysReg {
-  const char *Name;
-  const char *AltName;
-  const char *DeprecatedName;
+  const char Name[32];
+  const char AltName[32];
+  const char DeprecatedName[32];
   unsigned Encoding;
   // FIXME: add these additional fields when needed.
   // Privilege Access: Read, Write, Read-Only.