Type mismatch corrections (Windows 64 bits)

This patch removes the type mismatch warnings revealed by Windows 64
compiler.  Wherever necessary, used size_t type for size related data.

Change-Id: Ie045ce95940cd83fe8d681168ac9526fc6028d43
Signed-off-by: Patrick Benavoli <patrick.benavoli@intel.com>
diff --git a/parameter/Subsystem.cpp b/parameter/Subsystem.cpp
index fc54695..5dbe3a0 100644
--- a/parameter/Subsystem.cpp
+++ b/parameter/Subsystem.cpp
@@ -175,8 +175,8 @@
     _contextStack.push(context);
 
     // Map all instantiated subelements in subsystem
-    uint32_t uiNbChildren = getNbChildren();
-    uint32_t uiChild;
+    size_t uiNbChildren = getNbChildren();
+    size_t uiChild;
 
     for (uiChild = 0; uiChild < uiNbChildren; uiChild++) {