File fix-pc-file-paths.patch of Package fish3

Index: fish-3.1.2/cmake/Install.cmake
===================================================================
--- fish-3.1.2.orig/cmake/Install.cmake
+++ fish-3.1.2/cmake/Install.cmake
@@ -25,15 +25,15 @@ SET(configure_input
  DO NOT MANUALLY EDIT THIS FILE!")
 
 SET(extra_completionsdir
-    /usr/local/share/fish/vendor_completions.d
+    ${CMAKE_INSTALL_FULL_DATADIR}/fish/vendor_completions.d
     CACHE STRING "Path for extra completions")
 
 SET(extra_functionsdir
-    /usr/local/share/fish/vendor_functions.d
+    ${CMAKE_INSTALL_FULL_DATADIR}/fish/vendor_functions.d
     CACHE STRING "Path for extra functions")
 
 SET(extra_confdir
-    /usr/local/share/fish/vendor_conf.d
+    ${CMAKE_INSTALL_FULL_DATADIR}/fish/vendor_conf.d
     CACHE STRING "Path for extra configuration")
 
 # These are the man pages that go in system manpath; all manpages go in the fish-specific manpath.