Make mkdirAndChown do what it claims to do

Currently, mkdirAndChown takes parameters for mode, uid and gid, but
ignores them and hardcodes 0750, AID_SYSTEM, AID_SYSTEM instead.
This doesn't matter much because so far its only invocation passes
exactly those values as parameters -- but clang complains about unused
parameters.

Might as well make the function do what it claims to do.

Change-Id: I5a8056be3278a0c5d0a576dbc061288aa0956a35
Signed-off-by: Bernhard Rosenkränzer <Bernhard.Rosenkranzer@linaro.org>
diff --git a/libprocessgroup/processgroup.cpp b/libprocessgroup/processgroup.cpp
index 49f5903..71c065e 100644
--- a/libprocessgroup/processgroup.cpp
+++ b/libprocessgroup/processgroup.cpp
@@ -279,12 +279,12 @@
 {
     int ret;
 
-    ret = mkdir(path, 0750);
+    ret = mkdir(path, mode);
     if (ret < 0 && errno != EEXIST) {
         return -errno;
     }
 
-    ret = chown(path, AID_SYSTEM, AID_SYSTEM);
+    ret = chown(path, uid, gid);
     if (ret < 0) {
         ret = -errno;
         rmdir(path);