feat(disasm): name the CLDEMOTE encoding the decoder refuses

The hint NOP opcode 0F 1C /r with a memory operand is CLDEMOTE, a
memory-only instruction the toolchain's own table carries; the decoder
rejects the encoding instead of naming it.  The rejected-encoding side
of the supplementary table names it from the bytes, and the corpus row
0f1c03 pins the text in the unlisted fixture, round trip byte exact.

Assisted-by: GLM 5.3 Flash

disasm/naming_amd64_test.go

@@ -76,6 +76,10 @@ func TestDegenerateNaming(t *testing.T) {
 		// toolchain spelling.
 		{[]byte{0xf3, 0x0f, 0x1e, 0xfa}, "ENDBR64"},
 		{[]byte{0xf3, 0x0f, 0x1e, 0xfb}, "ENDBR32"},
+		// amd64enc_extra.s: CLDEMOTE (BX) // 0f1c03.  The decoder
+		// rejects the encoding outright; the table names it from the
+		// bytes.
+		{[]byte{0x0f, 0x1c, 0x03}, "CLDEMOTE 0(BX)"},
 	} {
 		ins, err := Decode(arch.AMD64, tt.code, 0)
 		if err != nil {
@@ -102,12 +106,13 @@ func TestDegenerateNamingBoundaries(t *testing.T) {
 		text string
 	}{
 		// Rejected outright: RDSEED without the operand-size override
-		// (the bare 0F C7 /7 register form), MONITORX and MWAITX, the
-		// hint NOP CLDEMOTE.
+		// (the bare 0F C7 /7 register form), MONITORX and MWAITX, and
+		// the register form of the hint NOP opcode, which the corpus
+		// does not spell.
 		{[]byte{0x0f, 0xc7, 0xfa}, "???"},
 		{[]byte{0x0f, 0x01, 0xfa}, "???"},
 		{[]byte{0x0f, 0x01, 0xfb}, "???"},
-		{[]byte{0x0f, 0x1c, 0x03}, "???"},
+		{[]byte{0x0f, 0x1c, 0xc3}, "???"},
 		// Degenerate but outside the table's prefix gates: repne ADCX is
 		// no instruction the corpus names.
 		{[]byte{0xf2, 0x0f, 0x38, 0xf6, 0xd2}, "REPNE; Op(0)"},