fix(asm): reject the arm64 REGTMP spellings the toolchain refuses

Assisted-by: GLM 5.3

asm/arm64_errorparity_test.go

@@ -20,13 +20,6 @@ var arm64AcceptedErrorShapes = []string{
 	// spelling, the .P immediate against the aggregate register size, the
 	// REGTMP (R27) as an explicit operand the toolchain refuses, the pair
 	// split paths included.
-	"ADD $0x1234567, R27, R3",
-	"ADD $0x3fffffffc000, R27, R5",
-	"AND $0x22220000, R27, R4",
-	"ANDW $0x6006000060060, R27, R5",
-	"STP (R3, R4), 0x1234567(R27)",
-	"LDP 0x1234567(R27), (R3, R4)",
-	"STP (R26, R27), 700(R2)",
 	// TLBI operand arity and the range-prefetch operand shapes.
 	"TLBI VMALLE1IS, R0",
 	"TLBI ALLE3OS, ZR",