translate-c: take address of functions before passing them to @ptrToInt

Fixes #12194

test/run_translated_c.zig

@@ -1861,4 +1861,18 @@ pub fn addCases(cases: *tests.RunTranslatedCContext) void {
         \\    return 0;
         \\}
     , "");
+
+    // The C standard does not require function pointers to be convertible to any integer type.
+    // However, POSIX requires that function pointers have the same representation as `void *`
+    // so that dlsym() can work
+    cases.add("Function to integral",
+        \\#include <stdint.h>
+        \\int main(void) {
+        \\#if defined(__UINTPTR_MAX__) && __has_include(<unistd.h>)
+        \\    uintptr_t x = main;
+        \\    x = (uintptr_t)main;
+        \\#endif
+        \\    return 0;
+        \\}
+    , "");
 }