[source] tools: cmake: fix librt linking (FS#1032)

[LEDE Commits]

jow pushed a commit to source.git, branch master:
https://git.lede-project.org/64da598c8f8bc3002ae2e8f90f0cf20986493348

commit 64da598c8f8bc3002ae2e8f90f0cf20986493348
Author: Jo-Philipp Wich <jo at mein.io>
AuthorDate: Mon Oct 2 13:56:50 2017 +0200

    tools: cmake: fix librt linking (FS#1032)
    
    Commit 839129b864 "tools/cmake: Update to 3.9.3" improperly rebased the
    librt linking patch, causing FS#381 to resurface.
    
    Fixes FS#1032.
    
    Signed-off-by: Jo-Philipp Wich <jo at mein.io>
---
 tools/cmake/patches/130-curl-fix-libressl-linking.patch | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/tools/cmake/patches/130-curl-fix-libressl-linking.patch b/tools/cmake/patches/130-curl-fix-libressl-linking.patch
index 1a15ff4..b5ee61b 100644
--- a/tools/cmake/patches/130-curl-fix-libressl-linking.patch
+++ b/tools/cmake/patches/130-curl-fix-libressl-linking.patch
@@ -20,14 +20,14 @@ Signed-off-by: Jo-Philipp Wich <jo at mein.io>
 ---
 --- a/Utilities/cmcurl/CMakeLists.txt
 +++ b/Utilities/cmcurl/CMakeLists.txt
-@@ -471,6 +471,10 @@ if(CMAKE_USE_OPENSSL)
-   check_symbol_exists(RAND_status "${CURL_INCLUDES}" HAVE_RAND_STATUS)
-   check_symbol_exists(RAND_screen "${CURL_INCLUDES}" HAVE_RAND_SCREEN)
-   check_symbol_exists(RAND_egd    "${CURL_INCLUDES}" HAVE_RAND_EGD)
+@@ -456,6 +456,10 @@ 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()
- 
-   # Optionally build with a specific CA cert bundle.
-   if(CURL_CA_BUNDLE)
+   list(APPEND CURL_LIBS ${OPENSSL_LIBRARIES})
+   include_directories(${OPENSSL_INCLUDE_DIR})
+   set(CMAKE_REQUIRED_INCLUDES ${OPENSSL_INCLUDE_DIR})