MLCE-500 Link zlib library to ArmNN

 * Bug fix: link only on Android

Signed-off-by: Keith Davis <keith.davis@arm.com>
Change-Id: I9f13da41bea9ffc72b75f21cef4faf1902341100
diff --git a/cmake/GlobalConfig.cmake b/cmake/GlobalConfig.cmake
index 0a9341f..8757723 100644
--- a/cmake/GlobalConfig.cmake
+++ b/cmake/GlobalConfig.cmake
@@ -66,7 +66,6 @@
 
 # Compiler flags that are always set
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
-set(CMAKE_EXE_LINKER_FLAGS  "${CMAKE_EXE_LINKER_FLAGS} -lz") # Necessary for when building with ACL set with compressed kernels
 if(COMPILER_IS_GNU_LIKE)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14 -Wall -Wextra -Werror -Wold-style-cast -Wno-missing-braces -Wconversion -Wsign-conversion")
 elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL MSVC)
@@ -75,8 +74,9 @@
     add_definitions(-DNO_STRICT=1)
 endif()
 if("${CMAKE_SYSTEM_NAME}" STREQUAL Android)
-    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -llog")
-    set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -llog")
+    # -lz is necessary for when building with ACL set with compressed kernels
+    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -llog -lz")
+    set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -llog -lz")
 endif()
 
 # Compiler flags for Release builds