fix issue loading binary pbm

drivers/pnm/bitmap_loader_pnm.cpp

@@ -170,12 +170,15 @@ RES ResourceFormatPBM::load(const String &p_path,const String& p_original_path,E
 		}
 
 		DVector<uint8_t>::Read r=token.read();
-
+		int bitwidth = width;
+		if (bidtwidth % 8)
+			bitwidth+=8-(bitwidth%8);
+			
 		for(int i=0;i<height;i++) {
 			for(int j=0;j<width;j++) {
 
 
-				char num = r[i*width+j];
+				char num = r[i*bitwidth+j];
 				bm->set_bit(Point2i(j,i),num=='0');
 			}