Change deprecated exec_program to execute_process in iOS.cmake

See CMP0153

CMake/iOS.cmake

@@ -45,7 +45,7 @@ set (CMAKE_OSX_DEPLOYMENT_TARGET "" CACHE STRING "Force unset of the deployment
 # Determine the cmake host system version so we know where to find the iOS SDKs
 find_program (CMAKE_UNAME uname /bin /usr/bin /usr/local/bin)
 if (CMAKE_UNAME)
-    exec_program(uname ARGS -r OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_VERSION)
+    execute_process(COMMAND uname -r OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
     string (REGEX REPLACE "^([0-9]+)\\.([0-9]+).*$" "\\1" DARWIN_MAJOR_VERSION "${CMAKE_HOST_SYSTEM_VERSION}")
 endif (CMAKE_UNAME)
 
@@ -163,7 +163,7 @@ set (IOS_DEPLOYMENT_TARGET ${IOS_DEPLOYMENT_TARGET} CACHE STRING "Minimum iOS ve
 
 # Setup iOS developer location unless specified manually with CMAKE_IOS_DEVELOPER_ROOT
 # Note Xcode 4.3 changed the installation location, choose the most recent one available
-exec_program(/usr/bin/xcode-select ARGS -print-path OUTPUT_VARIABLE CMAKE_XCODE_DEVELOPER_DIR)
+execute_process(COMMAND /usr/bin/xcode-select -print-path OUTPUT_VARIABLE CMAKE_XCODE_DEVELOPER_DIR OUTPUT_STRIP_TRAILING_WHITESPACE)
 set (XCODE_POST_43_ROOT "${CMAKE_XCODE_DEVELOPER_DIR}/Platforms/${IOS_PLATFORM_LOCATION}/Developer")
 set (XCODE_PRE_43_ROOT "/Developer/Platforms/${IOS_PLATFORM_LOCATION}/Developer")
 if (NOT DEFINED CMAKE_IOS_DEVELOPER_ROOT)