Update libxdiff patch.

Thanks to Mathieu Bridon

libgit2-0.20.0-system-libxdiff.patch

@@ -1,25 +1,25 @@
 diff --git a/CMakeLists.txt b/CMakeLists.txt
-index b931dc5..2aa8fde 100644
+index 6642290..70b013e 100644
 --- a/CMakeLists.txt
 +++ b/CMakeLists.txt
-@@ -298,7 +298,7 @@ ELSEIF (AMIGA)
+@@ -338,7 +338,7 @@ ELSEIF (AMIGA)
  ELSE()
- 	FILE(GLOB SRC_OS src/unix/*.c)
+ 	FILE(GLOB SRC_OS src/unix/*.c src/unix/*.h)
  ENDIF()
--FILE(GLOB SRC_GIT2 src/*.c src/transports/*.c src/xdiff/*.c)
+-FILE(GLOB SRC_GIT2 src/*.c src/*.h src/transports/*.c src/transports/*.h src/xdiff/*.c src/xdiff/*.h)
-+FILE(GLOB SRC_GIT2 src/*.c src/transports/*.c)
++FILE(GLOB SRC_GIT2 src/*.c src/*.h src/transports/*.c src/transports/*.h)
  
  # Determine architecture of the machine
  IF (CMAKE_SIZEOF_VOID_P EQUAL 8)
-@@ -313,6 +313,7 @@ ENDIF()
+@@ -353,6 +353,7 @@ ENDIF()
- ADD_LIBRARY(git2 ${SRC_GIT2} ${SRC_OS} ${SRC_ZLIB} ${SRC_HTTP} ${SRC_REGEX} ${SRC_SHA1} ${WIN_RC})
+ ADD_LIBRARY(git2 ${SRC_H} ${SRC_GIT2} ${SRC_OS} ${SRC_ZLIB} ${SRC_HTTP} ${SRC_REGEX} ${SRC_SHA1} ${WIN_RC})
  TARGET_LINK_LIBRARIES(git2 ${SSL_LIBRARIES})
  TARGET_LINK_LIBRARIES(git2 ${SSH_LIBRARIES})
 +TARGET_LINK_LIBRARIES(git2 -lxdiff)
  TARGET_OS_LIBRARIES(git2)
  
  # Workaround for Cmake bug #0011240 (see http://public.kitware.com/Bug/view.php?id=11240)
-@@ -388,6 +389,7 @@ IF (BUILD_CLAR)
+@@ -418,6 +419,7 @@ IF (BUILD_CLAR)
  
  	TARGET_LINK_LIBRARIES(libgit2_clar ${SSL_LIBRARIES})
  	TARGET_LINK_LIBRARIES(libgit2_clar ${SSH_LIBRARIES})

libgit2.spec

@@ -10,7 +10,7 @@ URL: http://libgit2.github.com/
 Source0: https://github.com/%{name}/%{name}/archive/%{commit}/%{name}-%{version}.tar.gz
 
 # Use system libxdiff
-Patch0: libgit2-0.19.0-system-libxdiff.patch
+Patch0: libgit2-0.20.0-system-libxdiff.patch
 
 # Add htonl() and friends declarations on non-x86 arches
 Patch1: libgit2-0.19.0-non-x86.patch