Description: Fixes build failure with gcc-7.1 :

dcraw.cc:9245:16: error: call of overloaded 'abs(unsigned int&)' is ambiguous
       if (abs(i) < abs(c)) {

This was a speculative change to get it to build - I have no idea what that
particular hunk of ocde does, but this seems to match the current version of
dcraw.c (9.27).

--- ufraw-0.22/dcraw.cc.orig	2017-05-15 03:52:55.360068631 +0100
+++ ufraw-0.22/dcraw.cc	2017-05-15 04:06:36.962790098 +0100
@@ -8766,8 +8766,8 @@
       "Nikon", "Nokia", "Olympus", "Pentax", "Phase One", "Ricoh",
       "Samsung", "Sigma", "Sinar", "Sony" };
   char head[32], *cp;
-  unsigned fsize, i, c;
-  int hlen, flen, zero_fsize=1;
+  unsigned fsize;
+  int hlen, flen, zero_fsize=1, i, c;
   struct jhead jh;
 
   tiff_flip = flip = filters = UINT_MAX;	/* unknown */