fix #19349 incompatible type when mixing float32 and cfloat in generics (#20551)

(cherry picked from commit 84fab7f39b)

tests/alias/t19349.nim

@@ -0,0 +1,19 @@
+discard """
+  action: "compile"
+"""
+
+type
+  Vec3[T: SomeNumber] = object
+    arr: array[3, T]
+
+var 
+  cfloatArr: array[3, array[3, cfloat]]
+  cfloatSeq = newSeq[Vec3[cfloat]]()
+for row in cfloatArr:
+  cfloatSeq.add(Vec3[float32](arr: [row[0], row[1], row[2]]))
+
+var 
+  cuintArr: array[3, array[3, cuint]]
+  cuintSeq = newSeq[Vec3[cuint]]()
+for row in cuintArr:
+  cuintSeq.add(Vec3[uint32](arr: [row[0], row[1], row[2]]))