[FunC] Require parenthesis in tricky bitwise precedence cases

Example: "flags & 0xFF != 0" is equivalent to "flags & 1",
most likely it's unexpected.
Example: "a << 2 + 1" (equal to "a << 3", probably unexpected).

The only way to suppress this error for the programmer
is to use parenthesis.

crypto/func/auto-tests/tests/invalid-bitwise-4.fc

@@ -0,0 +1,6 @@
+const a = (1) <=> (0) ^ 8;
+
+{-
+@compilation_should_fail
+@stderr ^ has lower precedence than <=>
+-}