+ completed Risc-V 64 pseudo instructions

  * typo fixed

compiler/riscv/cpubase.pas

@@ -60,7 +60,7 @@ uses
         { 64-bit }
         A_ADDIW,A_SLLIW,A_SRLIW,A_SRAIW,
         A_ADDW,A_SLLW,A_SRLW,A_SUBW,A_SRAW,
-        A_LD,A_SD,A_LWU,
+        A_LD,A_SD,A_LWU,A_SEXT_W,A_ZEXT_W,
 {$endif RISCV64}
 
         { M-extension }

compiler/riscv/itcpugas.pas

@@ -31,7 +31,7 @@ unit itcpugas;
     const
       gas_op2str: array[tasmop] of string[14] = ('<none>',
         'nop','call','la','lla','lga','li','mv','not','neg','negw',
-        'sext.b','sext.h','zext.b','zex.h','seqz','sneg','sltz','sgtz',
+        'sext.b','sext.h','zext.b','zext.h','seqz','sneg','sltz','sgtz',
         'fmv.s','fabs.s','fneg.s','fmv.d','fabs.d','fneg.d',
         'beqz','bnez','blez','bgez','bltz','bgtz','gt','ble',
         'bgtu','bleu','j','jr','ret','tail',
@@ -50,7 +50,8 @@ unit itcpugas;
         { 64-bit }
         'addiw','slliw','srliw','sraiw',
         'addw','sllw','srlw','subw','sraw',
-        'ld','sd','lwu',
+        { pseudo instructions }
+        'ld','sd','lwu','sext.w','zext.w',
 {$endif RISCV64}
 
         { m-extension }