[RISCV][NFC] Remove rdty arg of PseudoLoad and the default rdty value of PseudoFloatLoad (#67014)

`rdty` of `PseudoLoad` is always `GPR` and it will never be `GPR` for
`PseudoFloatLoad`.

Author: wangpc-pp

llvm/lib/Target/RISCV/RISCVInstrFormats.td

@@ -241,16 +241,16 @@ class PseudoQuietFCMP<DAGOperand Ty>
 }
 
 // Pseudo load instructions.
-class PseudoLoad<string opcodestr, RegisterClass rdty = GPR>
-    : Pseudo<(outs rdty:$rd), (ins bare_symbol:$addr), [], opcodestr, "$rd, $addr"> {
+class PseudoLoad<string opcodestr>
+    : Pseudo<(outs GPR:$rd), (ins bare_symbol:$addr), [], opcodestr, "$rd, $addr"> {
   let hasSideEffects = 0;
   let mayLoad = 1;
   let mayStore = 0;
   let isCodeGenOnly = 0;
   let isAsmParserOnly = 1;
 }
 
-class PseudoFloatLoad<string opcodestr, RegisterClass rdty = GPR>
+class PseudoFloatLoad<string opcodestr, RegisterClass rdty>
     : Pseudo<(outs GPR:$tmp, rdty:$rd), (ins bare_symbol:$addr), [], opcodestr, "$rd, $addr, $tmp"> {
   let hasSideEffects = 0;
   let mayLoad = 1;