Include what you use: <unistd.h>

This was transitively included, but no longer is, so it must be
explicitly included.

Exempt-From-Owner-Approval: Janitorial
Test: build
Change-Id: I78268a4867697bf797d40b5fead3745fdd0cc807
diff --git a/camera/CameraParameters.cpp b/camera/CameraParameters.cpp
index 68969cf..e95c91c 100644
--- a/camera/CameraParameters.cpp
+++ b/camera/CameraParameters.cpp
@@ -20,6 +20,7 @@
 
 #include <string.h>
 #include <stdlib.h>
+#include <unistd.h>
 #include <camera/CameraParameters.h>
 #include <system/graphics.h>