ssa: fix map key has typeargs

cl/_testrt/tpmap/in.go

@@ -0,0 +1,26 @@
+package main
+
+type T1 int
+
+type T2 struct {
+	v int
+}
+
+type T3[T any] struct {
+	v T
+}
+
+type cacheKey struct {
+	t1 T1
+	t2 T2
+	t3 T3[any]
+	t4 *int
+	t5 uintptr
+}
+
+func main() {
+	m := map[cacheKey]string{}
+	m[cacheKey{0, T2{0}, T3[any]{0}, nil, 0}] = "world"
+	v, ok := m[cacheKey{0, T2{0}, T3[any]{0}, nil, 0}]
+	println(v, ok)
+}