Add Svadu Extension Parsing to ISA Parser

Make the ISA parser understand the Svadu extension.

riscv/isa_parser.cc

@@ -206,6 +206,8 @@ isa_parser_t::isa_parser_t(const char* str, const char *priv)
       extension_table[EXT_SMSTATEEN] = true;
     } else if (ext_str == "sscofpmf") {
       extension_table[EXT_SSCOFPMF] = true;
+    } else if (ext_str == "svadu") {
+      extension_table[EXT_SVADU] = true;
     } else if (ext_str == "svnapot") {
       extension_table[EXT_SVNAPOT] = true;
     } else if (ext_str == "svpbmt") {

riscv/isa_parser.h

@@ -42,6 +42,7 @@ typedef enum {
   EXT_SMEPMP,
   EXT_SMSTATEEN,
   EXT_SSCOFPMF,
+  EXT_SVADU,
   EXT_SVNAPOT,
   EXT_SVPBMT,
   EXT_SVINVAL,