Improve help description

Author: gephaistos

src/main.rs

@@ -204,7 +204,9 @@ fn run() -> Result<()> {
                 .long("base-address-shift")
                 .alias("base_address_shift")
                 .action(ArgAction::Set)
-                .help("Shift base address for all peripherals"),
+                .help("Add offset to all base addresses on all peripherals in the SVD file.
+                Useful for soft-cores where the peripheral address range isn't necessarily fixed.
+                Ignore this option if you are not building your own FPGA based soft-cores."),
         )
         .arg(
             Arg::new("log_level")