[new uImage] Move gunzip() common code to common/gunzip.c

Move gunzip(), zalloc() and zfree() to a separate file.
Share zalloc() and zfree() with cramfs uncompress routine.

Signed-off-by: Marian Balakowicz <m8@semihalf.com>
diff --git a/lib_generic/bzlib.c b/lib_generic/bzlib.c
index 87e6a6e..0d3f9c2 100644
--- a/lib_generic/bzlib.c
+++ b/lib_generic/bzlib.c
@@ -1592,6 +1592,10 @@
 }
 #endif
 
+void bz_internal_error(int errcode)
+{
+	printf ("BZIP2 internal error %d\n", errcode);
+}
 
 /*-------------------------------------------------------------*/
 /*--- end                                           bzlib.c ---*/