Add Svade extension Support

Spike always supports the Svade extension, this is required by the RVA and RVB profiles

README.md

@@ -40,6 +40,7 @@ Spike supports the following RISC-V ISA features:
   - Svpbmt extension, v1.0
   - Svinval extension, v1.0
   - Svadu extension, v1.0
+  - Svade extension, v1.0
   - Sdext extension, v1.0-STABLE
   - Sdtrig extension, v1.0-STABLE
   - Smepmp extension v1.0

disasm/isa_parser.cc

@@ -244,6 +244,8 @@ isa_parser_t::isa_parser_t(const char* str, const char *priv)
       extension_table[EXT_SSCOFPMF] = true;
     } else if (ext_str == "svadu") {
       extension_table[EXT_SVADU] = true;
+    } else if (ext_str == "svade") {
+      extension_table[EXT_SVADE] = true;
     } else if (ext_str == "svnapot") {
       extension_table[EXT_SVNAPOT] = true;
     } else if (ext_str == "svpbmt") {

riscv/isa_parser.h

@@ -40,6 +40,7 @@ typedef enum {
   EXT_SMRNMI,
   EXT_SSCOFPMF,
   EXT_SVADU,
+  EXT_SVADE,
   EXT_SVNAPOT,
   EXT_SVPBMT,
   EXT_SVINVAL,