Use intptr_t when storing an integer in a pointer

Cast the integer type to (u)intptr_t before casting to "void *".  In
CHERI C/C++ we warn on bare casts from integers to pointers to catch
attempts to create pointers our of thin air.  We allow the warning to be
supressed with a suitable cast through (u)intptr_t.

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Brooks Davis <brooks.davis@sri.com>
Closes #14131

cmd/zstream/zstream_decompress.c

@@ -146,7 +146,7 @@ zstream_do_decompress(int argc, char *argv[])
 		p = hsearch(e, ENTER);
 		if (p == NULL)
 			errx(1, "hsearch");
-		p->data = (void*)type;
+		p->data = (void*)(intptr_t)type;
 	}
 
 	if (isatty(STDIN_FILENO)) {

module/zfs/zfs_vnops.c

@@ -64,7 +64,7 @@ zfs_fsync(znode_t *zp, int syncflag, cred_t *cr)
 	int error = 0;
 	zfsvfs_t *zfsvfs = ZTOZSB(zp);
 
-	(void) tsd_set(zfs_fsyncer_key, (void *)zfs_fsync_sync_cnt);
+	(void) tsd_set(zfs_fsyncer_key, (void *)(uintptr_t)zfs_fsync_sync_cnt);
 
 	if (zfsvfs->z_os->os_sync != ZFS_SYNC_DISABLED) {
 		if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)