Add default Fedora/Debian locations for CXSparse to search paths.

Change-Id: I7361ae3e821eb1f481b28dc9b94f57cb5eb0093f
diff --git a/cmake/FindCXSparse.cmake b/cmake/FindCXSparse.cmake
index ce01199..718042c 100644
--- a/cmake/FindCXSparse.cmake
+++ b/cmake/FindCXSparse.cmake
@@ -129,11 +129,15 @@
   /usr/local/homebrew/include # Mac OS X
   /opt/local/var/macports/software # Mac OS X.
   /opt/local/include
+  /usr/local/include/suitesparse # Linux.
+  /usr/include/suitesparse # Linux.
   /usr/include)
 list(APPEND CXSPARSE_CHECK_LIBRARY_DIRS
   /usr/local/lib
   /usr/local/homebrew/lib # Mac OS X.
   /opt/local/lib
+  /usr/local/lib/suitesparse # Linux.
+  /usr/lib/suitesparse # Linux.
   /usr/lib)
 
 # Search supplied hint directories first if supplied.