main: In help output, show how to detect flash

Author: UweBonnes

README.md

@@ -71,7 +71,7 @@ openFPGALoader -- a program to flash FPGA
       --ftdi-serial arg         FTDI chip serial number
       --ftdi-channel arg        FTDI chip channel number (channels 0-3 map to
                                 A-D)
-      --detect                  detect FPGA
+      --detect                  detect FPGA, add -f to show connected flash
       --dfu                     DFU mode
       --dump-flash              Dump flash mode
       --bulk-erase              Bulk erase flash

src/main.cpp

@@ -763,7 +763,7 @@ int parse_opt(int argc, char **argv, struct arguments *args,
 			("d,device",  "device to use (/dev/ttyUSBx)",
 				cxxopts::value<string>(args->device))
 #endif
-			("detect",      "detect FPGA",
+			("detect",      "detect FPGA, add -f to show connected flash",
 				cxxopts::value<bool>(args->detect))
 			("dfu",   "DFU mode", cxxopts::value<bool>(args->dfu))
 			("dump-flash",  "Dump flash mode")