checkpatch: improve TYPECAST_INT_CONSTANT test message

Improve the TYPECAST_INT_CONSTANT test by showing the suggested conversion
for various type of uses like (unsigned int)1 to 1U.

Link: https://lkml.kernel.org/r/ecefe8dcb93fe7028311b69dd297ba52224233d4.camel@perches.com


Signed-off-by: Joe Perches <joe@perches.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>