ufraw: fix gcc7 build

srcpkgs/ufraw/patches/002-fix_abs_int.patch

@@ -0,0 +1,11 @@
+--- dcraw.cc	2015-06-16 05:58:38.000000000 +0200
++++ dcraw.cc	2018-02-04 14:46:54.489951076 +0100
+@@ -9242,7 +9242,7 @@
+     if (make[0] == 'O') {
+       i = find_green (12, 32, 1188864, 3576832);
+       c = find_green (12, 32, 2383920, 2387016);
+-      if (abs(i) < abs(c)) {
++      if (abs((int)i) < abs((int)c)) {
+ 	SWAP(i,c);
+ 	load_flags = 24;
+       }