perf/core: Fix address filter parser for multiple filters

Reset appropriate variables in the parser loop between parsing separate
filters, so that they do not interfere with parsing the next filter.

Fixes: 375637b ("perf/core: Introduce address range filtering")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220131072453.2839535-4-adrian.hunter@intel.com

Author: ahunter6

kernel/events/core.c

@@ -10558,8 +10558,11 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr,
 			}
 
 			/* ready to consume more filters */
+			kfree(filename);
+			filename = NULL;
 			state = IF_STATE_ACTION;
 			filter = NULL;
+			kernel = 0;
 		}
 	}