get_key_material_https: removed bogus free() call

The get_key_material_https() function error code path had a bogus
free() call, either resulting in double-free or free() of undefined
pointer.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ahelenia Ziemia<C5><84>ska <nabijaczleweli@nabijaczleweli.xyz>
Co-authored-by: Harry Sintonen <sintonen@iki.fi>
Signed-off-by: Harry Sintonen <sintonen@iki.fi>
Closes #13198

lib/libzfs/libzfs_crypto.c

@@ -606,7 +606,6 @@ get_key_material_https(libzfs_handle_t *hdl, const char *uri,
 kfdok:
 	if ((key = fdopen(kfd, "r+")) == NULL) {
 		ret = errno;
-		free(path);
 		(void) close(kfd);
 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 		    "Couldn't reopen temporary file: %s"), strerror(ret));