tools/libressl: update to version 2.7.2

Libressl version 2.7.0 and later implement more of the OpenSSL 1.1 API
and this needs some modifications of the code using it.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

tools/cmake/patches/120-curl-fix-libressl-linking.patch

@@ -20,13 +20,17 @@ Signed-off-by: Jo-Philipp Wich <jo@mein.io>
 ---
 --- a/Utilities/cmcurl/CMakeLists.txt
 +++ b/Utilities/cmcurl/CMakeLists.txt
-@@ -461,6 +461,10 @@ if(CMAKE_USE_OPENSSL)
+@@ -461,6 +461,14 @@ if(CMAKE_USE_OPENSSL)
    set(USE_OPENSSL ON)
    set(HAVE_LIBCRYPTO ON)
    set(HAVE_LIBSSL ON)
 +  check_library_exists("rt" clock_gettime "" HAVE_LIBRT)
 +  if(HAVE_LIBRT)
 +    list(APPEND OPENSSL_LIBRARIES rt)
++  endif()
++  check_library_exists("pthread" pthread_once "" HAVE_PTHREAD)
++  if(HAVE_PTHREAD)
++    list(APPEND OPENSSL_LIBRARIES pthread)
 +  endif()
    list(APPEND CURL_LIBS ${OPENSSL_LIBRARIES})
    include_directories(${OPENSSL_INCLUDE_DIR})