Fix ncurses lookup on Arch Linux

Arch Linux doesn't put it's ncursesw includes inside an ncursesw
directory.  This script ends up setting USE_CURSES as true, but
doesn't pick up any of the headers.

https://bugs.archlinux.org/task/13994

cmake/Modules/FindNcursesw.cmake

@@ -147,6 +147,21 @@ if(CURSES_USE_NCURSESW)
       set(CURSES_HAVE_NCURSESW_CURSES_H "CURSES_HAVE_NCURSESW_CURSES_H-NOTFOUND")
     endif()
   endif()
+  if(NOT DEFINED CURSES_HAVE_NCURSES_H)
+    if(EXISTS "${CURSES_INCLUDE_PATH}/ncurses.h")
+      set(CURSES_HAVE_NCURSES_H "${CURSES_INCLUDE_PATH}/ncurses.h")
+    else()
+      set(CURSES_HAVE_NCURSES_H "CURSES_HAVE_NCURSES_H-NOTFOUND")
+    endif()
+  endif()
+  if(NOT DEFINED CURSES_HAVE_CURSES_H)
+    if(EXISTS "${CURSES_INCLUDE_PATH}/curses.h")
+      set(CURSES_HAVE_CURSES_H "${CURSES_INCLUDE_PATH}/curses.h")
+    else()
+      set(CURSES_HAVE_CURSES_H "CURSES_HAVE_CURSES_H-NOTFOUND")
+    endif()
+  endif()
+
 
   find_library(CURSES_FORM_LIBRARY form HINTS "${_cursesLibDir}"
     DOC "Path to libform.so or .lib or .a")