Build fails on OS X

[IngwiePhoenix]

Hey there!

I did a blind try to build this library and got quite some errors. To reproduce:

• git clone https://github.com/libpdk/libpdk.git
• mkdir out
• cd out
• cmake ..

CMake fails with this:

-- Performing Test PDK_TEMP_C_SUPPORTS_C99 - Success
 -fPIC -Wall -W -Wno-unused-parameter -Wwrite-strings -Wmissing-field-initializers -pedantic -Wno-long-long -Wcovered-switch-default -Wdelete-non-virtual-dtor -Wstring-conversion -Werror=date-time -Wno-unused-function -Wno-unneeded-internal-declaration -Werror=unguarded-availability-new -std=c99
CMake Warning (dev) at thirdparty/zendapi/CMakeLists.txt:68 (option):
  Policy CMP0077 is not set: option() honors normal variables.  Run "cmake
  --help-policy CMP0077" for policy details.  Use the cmake_policy command to
  set the policy and suppress this warning.

  For compatibility with older versions of CMake, option is clearing the
  normal variable 'ZAPI_OPT_ENABLE_UNIT_TESTS'.
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at thirdparty/zendapi/CMakeLists.txt:71 (option):
  Policy CMP0077 is not set: option() honors normal variables.  Run "cmake
  --help-policy CMP0077" for policy details.  Use the cmake_policy command to
  set the policy and suppress this warning.

  For compatibility with older versions of CMake, option is clearing the
  normal variable 'ZAPI_OPT_ENABLE_RUNTIME_TESTS'.
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Error at thirdparty/zendapi/cmake/modules/DetectPhpInfo.cmake:34 (message):
  php library is not found automatic, maybe your php is not in system
  standard path you can specify ZAPI_OPT_PHPCFG_PATH and try again, good
  luck!
Call Stack (most recent call first):
  thirdparty/zendapi/CMakeLists.txt:138 (include)


-- Configuring incomplete, errors occurred!
See also "/Users/Ingwie/Work/Git/libpdk/out/CMakeFiles/CMakeOutput.log".
See also "/Users/Ingwie/Work/Git/libpdk/out/CMakeFiles/CMakeError.log".

Now, I installed PHP7 via Homebrew and this is where it is:

Ingwie@Ingwies-MBP.fritz.box ~/W/G/l/out $ which php-config
/usr/local/bin/php-config
Ingwie@Ingwies-MBP.fritz.box ~/W/G/l/out $ which php
/usr/local/bin/php
Ingwie@Ingwies-MBP.fritz.box ~/W/G/l/out $ which php-cli
Ingwie@Ingwies-MBP.fritz.box ~/W/G/l/out $ php --version
PHP 7.2.14 (cli) (built: Jan 12 2019 05:21:04) ( NTS )
Copyright (c) 1997-2018 The PHP Group
Zend Engine v3.2.0, Copyright (c) 1998-2018 Zend Technologies
    with Zend OPcache v7.2.14, Copyright (c) 1999-2018, by Zend Technologies
Ingwie@Ingwies-MBP.fritz.box ~/W/G/l/out $ php-config --version
7.2.14

So apparently, something is not working :)

Any hotfix I can apply to make this build?