[yaml2obj][wasm] Support numeric relocation type

[sbc100]

Oh nice! Thanks.

I'll use this to remove the checked in binaries where possible.

llvm/lib/ObjectYAML/WasmYAML.cpp

 #undef ECase
 }
 
 void ScalarEnumerationTraits<WasmYAML::RelocType>::enumeration(
     IO &IO, WasmYAML::RelocType &Type) {
 #define WASM_RELOC(name, value) IO.enumCase(Type, #name, wasm::name);
 #include "llvm/BinaryFormat/WasmRelocs.def"
 #undef WASM_RELOC
+  IO.enumFallback<Hex32>(Type);
 }
 
 } // end namespace yaml
 
 } // end namespace llvm

llvm/test/ObjectYAML/wasm/event_section.yaml

Events:
       - Index:           0
         Attribute:       0
         SigIndex:        1
   - Type:            CODE
     Relocations:
       - Type:            R_WASM_EVENT_INDEX_LEB
         Index:           1
         Offset:          0x00000006
+      - Type:            10
+        Index:           1
+        Offset:          0x00000006
     Functions:
       - Index:           0
         Locals:
         Body:            200008808080800041000B
   - Type:            CUSTOM
     Name:            linking
     Version:         2
     SymbolTable:

 # CHECK-NEXT:       - Index:           0
 # CHECK-NEXT:         Attribute:       0
 # CHECK-NEXT:         SigIndex:        1
 # CHECK-NEXT:   - Type:            CODE
 # CHECK-NEXT:     Relocations:
 # CHECK-NEXT:       - Type:            R_WASM_EVENT_INDEX_LEB
 # CHECK-NEXT:         Index:           1
 # CHECK-NEXT:         Offset:          0x6
+# CHECK-NEXT:       - Type:            R_WASM_EVENT_INDEX_LEB
+# CHECK-NEXT:         Index:           1
+# CHECK-NEXT:         Offset:          0x6
 # CHECK-NEXT:     Functions:
 # CHECK-NEXT:       - Index:           0
 # CHECK-NEXT:         Locals:
 # CHECK-NEXT:         Body:            200008808080800041000B
 # CHECK-NEXT:   - Type:            CUSTOM
 # CHECK-NEXT:     Name:            linking
 # CHECK-NEXT:     Version:         2
 # CHECK-NEXT:     SymbolTable: