tools: acrn-crashlog: fix some possible memory leak

This patch is to fix some possible memory leak issues, which are
reported by static analysis tool.

1. free uptime in error case handling of function parse_uptime.
2. unmap f in error case handling of function _file_read_key_value.

Tracked-On: #2917
Reviewed-by: Liu, Xinwu <xinwu.liu@intel.com>
Reviewed-by: Zhi Jin <zhi.jin@intel.com>
Signed-off-by: CHEN Gang <gang.c.chen@intel.com>
Acked-by: Zhang Di <di.zhang@intel.com>

Author: chengangc

tools/acrn-crashlog/acrnprobe/load_conf.c

@@ -629,14 +629,17 @@ static int parse_uptime(xmlNodePtr cur, struct sender_t *sender)
 		else if (name_is(cur, "eventhours"))
 			res = load_cur_content(cur, uptime, eventhours);
 
-		if (res)
+		if (res) {
+			free(uptime);
 			return -1;
+		}
 
 		cur = cur->next;
 	}
 	res = asprintf(&uptime->path, "%s/uptime", sender->outdir);
 	if (res < 0) {
 		LOGE("build string failed\n");
+		free(uptime);
 		return -1;
 	}
 	sender->uptime = uptime;

tools/acrn-crashlog/common/fsutils.c

@@ -686,12 +686,12 @@ static ssize_t _file_read_key_value(char *value, const size_t limit,
 		return -errno;
 	if (!key) {
 		errno = EINVAL;
-		return -errno;
+		goto unmap;
 	}
 
 	if (op != 'l' && op != 'r') {
 		errno = EINVAL;
-		return -errno;
+		goto unmap;
 	}
 
 	if (op == 'l')