cfdisk: add hint about labels for bootable flag

Addresses: #2220
Signed-off-by: Karel Zak <[email protected]>

disk-utils/cfdisk.c

@@ -1,7 +1,7 @@
 /*
  * cfdisk.c - Display or manipulate a disk partition table.
  *
- * Copyright (C) 2014-2015 Karel Zak <[email protected]>
+ * Copyright (C) 2014-2023 Karel Zak <[email protected]>
  * Copyright (C) 1994 Kevin E. Martin ([email protected])
  *
  * The original cfdisk was inspired by the fdisk program
@@ -2257,7 +2257,8 @@ static int ui_help(void)
  " ",
  N_("Command Meaning"),
  N_("------- -------"),
- N_(" b Toggle bootable flag of the current partition"),
+ N_(" b Toggle bootable flag of the current partition;"),
+ N_(" implemented for DOS (MBR) and SGI labels only"),
  N_(" d Delete the current partition"),
  N_(" h Print this screen"),
  N_(" n Create new partition from free space"),
@@ -2281,7 +2282,7 @@ static int ui_help(void)
  N_("Use lsblk(8) or partx(8) to see more details about the device."),
  " ",
  " ",
- "Copyright (C) 2014-2017 Karel Zak <[email protected]>"
+ "Copyright (C) 2014-2023 Karel Zak <[email protected]>"
  };
 
  erase();