[bwbar] fix build failure with new libpng

[Adrian Reber]

commit d362ff376b6cd83076df8bb969a786505bc2b182
Author: Adrian Reber <adrian at lisas.de>
Date:   Tue Dec 6 10:12:48 2011 +0100

    fix build failure with new libpng

 bwbar.zlib.h.patch |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)
---
diff --git a/bwbar.zlib.h.patch b/bwbar.zlib.h.patch
index 662e9f3..060ba80 100644
--- a/bwbar.zlib.h.patch
+++ b/bwbar.zlib.h.patch
@@ -8,3 +8,12 @@
  
  void skipline(FILE *f)
  {
+@@ -79,7 +80,7 @@
+   if ( !info_ptr )
+     goto barf;
+ 
+-  if ( setjmp(png_ptr->jmpbuf) ) {
++  if ( setjmp(png_jmpbuf((png_ptr))) ) {
+     status = 1;
+     goto barf;			/* libpng abort */
+   }