Compiling on arm64 freebsd-13.2 and arm64 almalinux-8 brings currently
this error:
```
CC tests/zfs-tests/cmd/clonefile.o
tests/zfs-tests/cmd/clonefile.c:166:43: error: result of comparison of \
constant -1 with expression of type 'char' is always true \
[-Werror,-Wtautological-constant-out-of-range-compare]
while ((c = getopt(argc, argv, "crfdq")) != -1) {
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~
1 error generated.
gmake[2]: *** [Makefile:8675: tests/zfs-tests/cmd/clonefile.o] Error 1
```
Fix: use correct variable type `int`.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Rob Norris <robn@despairlabs.com> Signed-off-by: Tino Reichardt <milky-zfs@mcmilk.de>
Closes #15783