Fix iOS CMake toolchain for newer versions of CMake (neoml-lib#1016)

Signed-off-by: Valery Fedyunin <valery.fedyunin@abbyy.com>
Signed-off-by: daniyalaliev <daniial.aliev@abbyy.com>

cmake/ios.toolchain.cmake

@@ -20,7 +20,7 @@ message(STATUS "Building with Xcode version: ${XCODE_VERSION}")
 # Determine the cmake host system version so we know where to find the iOS SDKs
 find_program(CMAKE_UNAME uname /bin /usr/bin /usr/local/bin)
 if(CMAKE_UNAME)
-    exec_program(uname ARGS -r OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_VERSION)
+    execute_process(COMMAND uname -r OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_VERSION)
     string (REGEX REPLACE "^([0-9]+)\\.([0-9]+).*$" "\\1" DARWIN_MAJOR_VERSION "${CMAKE_HOST_SYSTEM_VERSION}")
 endif(CMAKE_UNAME)