.gitignore: ignore *.tar

Running make tar-pkg results in following:

 # Untracked files:
 #   (use "git add <file>..." to include in what will be committed)
 #
 #       linux-4.0.0-rc3-next-20150313-150225--x86.tar

This patch makes git ignore *.tar files.
Running 'git ls-files -i --exclude-standard' does not show any
tar files excluded from tracking after the change.

Signed-off-by: Andrey Skvortsov <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Boaz Harrosh <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Benjamin Romer <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

.gitignore

@@ -24,6 +24,7 @@
 *.order
 *.elf
 *.bin
+*.tar
 *.gz
 *.bz2
 *.lzma