scripts/bloat-o-meter: fix SIGPIPE

Fix piping output to a program which quickly exits (read: head -n1)

	$ ./scripts/bloat-o-meter ../vmlinux-000 ../obj/vmlinux | head -n1
	add/remove: 0/0 grow/shrink: 9/60 up/down: 124/-305 (-181)
	close failed in file object destructor:
	sys.excepthook is missing
	lost sys.stderr

Link: http://lkml.kernel.org/r/20161028204618.GA29923@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/scripts/bloat-o-meter b/scripts/bloat-o-meter
index 19f5adf..d9ff038 100755
--- a/scripts/bloat-o-meter
+++ b/scripts/bloat-o-meter
@@ -8,6 +8,9 @@
 # of the GNU General Public License, incorporated herein by reference.
 
 import sys, os, re
+from signal import signal, SIGPIPE, SIG_DFL
+
+signal(SIGPIPE, SIG_DFL)
 
 if len(sys.argv) != 3:
     sys.stderr.write("usage: %s file1 file2\n" % sys.argv[0])