GIT: [PATCH] exec_cmd: system_path memory leak fix

Hello All,
I found memory leak at exec_cmd.c in system_path function with valgrind.
After this patch valgrind doesn't show any memory leaks, but I'm not sure
that it is the best way to solve this problem. There are a couple of places
that uses system_path, if this way will be good, i'll make another patches
to fix this leak.

Waiting for feedback.

Signed-off-by: Alex Kuleshov <redacted>