DO NOT MERGE Revert "[mypyc] Fix test case testI64Cast on 32-bit architectures (#14691)"

This reverts commit 563e29d to confirm
the fix is caught by CI

Author: mr-c

mypyc/test-data/irbuild-i64.test

@@ -1770,7 +1770,7 @@ L1:
 L2:
     return 1
 
-[case testI64Cast_64bit]
+[case testI64Cast]
 from typing import cast
 from mypy_extensions import i64
 
@@ -1811,39 +1811,6 @@ L2:
 L3:
     return r3
 
-[case testI64Cast_32bit]
-from typing import cast
-from mypy_extensions import i64
-
-def cast_int(x: int) -> i64:
-    return cast(i64, x)
-[out]
-def cast_int(x):
-    x :: int
-    r0 :: native_int
-    r1 :: bit
-    r2, r3, r4 :: int64
-    r5 :: ptr
-    r6 :: c_ptr
-    r7 :: int64
-L0:
-    r0 = x & 1
-    r1 = r0 == 0
-    if r1 goto L1 else goto L2 :: bool
-L1:
-    r2 = extend signed x: builtins.int to int64
-    r3 = r2 >> 1
-    r4 = r3
-    goto L3
-L2:
-    r5 = x ^ 1
-    r6 = r5
-    r7 = CPyLong_AsInt64(r6)
-    r4 = r7
-    keep_alive x
-L3:
-    return r4
-
 [case testI64ExplicitConversionFromVariousTypes]
 from mypy_extensions import i64