gitignore: Ignore KDE backup files

KDE editors love to create tons of backup files every time a file is
edited. This makes it very hard to get useful information from git status
and very easy to commit the wrong stuff. Add those to the gitignore list.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Change-Id: I2fbb907f21d85d6994caa8bbe32c4e9814b5f4b4
Reviewed-on: http://review.coreboot.org/1423
Reviewed-by: Peter Stuge <peter@stuge.se>
Tested-by: build bot (Jenkins)

.gitignore

@@ -35,6 +35,15 @@ util/crossgcc/w32api-*/
 *.\#
 *.swp
 *.bin
+
+#
+# KDE editors create lots of backup files whenever
+# a file is edited, so just ignore them
+*~
+*.kate-swp
+# Ignore Kdevelop project file
+.kdev4
+
 util/ectool/ectool
 util/inteltool/.dependencies
 util/inteltool/inteltool