graphics/hvif-tools: fix build on ARM / POWER

/wrkdirs/usr/ports/graphics/hvif-tools/work/hvif-tools-2.1.0/src/tracer/processing/PathScanner.cpp:20:4: error: constant expression evaluates to -1 which cannot be narrowed to type 'char' [-Wc++11-narrowing]
   20 |         {{-1,-1,-1,-1}, {-1,-1,-1,-1}, {-1,-1,-1,-1}, {-1,-1,-1,-1}}, // 0
      |           ^~
/wrkdirs/usr/ports/graphics/hvif-tools/work/hvif-tools-2.1.0/src/tracer/processing/PathScanner.cpp:20:4: note: insert an explicit cast to silence this issue
   20 |         {{-1,-1,-1,-1}, {-1,-1,-1,-1}, {-1,-1,-1,-1}, {-1,-1,-1,-1}}, // 0
      |           ^~
      |           static_cast<char>( )

graphics/hvif-tools/files/patch-src_tracer_processing_PathScanner.cpp

@@ -0,0 +1,20 @@
+--- src/tracer/processing/PathScanner.cpp.orig	2025-12-14 12:31:31 UTC
++++ src/tracer/processing/PathScanner.cpp
+@@ -16,7 +16,7 @@ const bool PathScanner::kPathScanHolePathLookup[16] = 
+ 	false, false, false, true, false, true, true, false
+ };
+ 
+-const char PathScanner::kPathScanCombinedLookup[16][4][4] = {
++const signed char PathScanner::kPathScanCombinedLookup[16][4][4] = {
+ 	{{-1,-1,-1,-1}, {-1,-1,-1,-1}, {-1,-1,-1,-1}, {-1,-1,-1,-1}}, // 0
+ 	{{ 0, 1, 0,-1}, {-1,-1,-1,-1}, {-1,-1,-1,-1}, { 0, 2,-1, 0}}, // 1
+ 	{{-1,-1,-1,-1}, {-1,-1,-1,-1}, { 0, 1, 0,-1}, { 0, 0, 1, 0}}, // 2
+@@ -137,7 +137,7 @@ PathScanner::ScanPaths(std::vector<std::vector<int> >&
+ 						break;
+ 					}
+ 
+-					const char* lookupRow = kPathScanCombinedLookup[code][direction];
++					const signed char* lookupRow = kPathScanCombinedLookup[code][direction];
+ 
+ 					if (lookupRow[1] < 0) {
+ 						pathFinished = true;

graphics/hvif-tools/files/patch-src_tracer_processing_PathScanner.h

@@ -0,0 +1,11 @@
+--- src/tracer/processing/PathScanner.h.orig	2025-12-14 12:31:58 UTC
++++ src/tracer/processing/PathScanner.h
+@@ -35,7 +35,7 @@ class PathScanner { (private)
+ private:
+ 	static const unsigned char	kPathScanDirectionLookup[16];
+ 	static const bool			kPathScanHolePathLookup[16];
+-	static const char			kPathScanCombinedLookup[16][4][4];
++	static const signed char			kPathScanCombinedLookup[16][4][4];
+ };
+ 
+ #endif