hexdump: fix man page (-x vs. default output)

Reported-by: Reuti <reuti@staff.uni-marburg.de>
Signed-off-by: Karel Zak <kzak@redhat.com>

text-utils/hexdump.1

@@ -335,10 +335,9 @@ conversion character or conversion string but with any
 .RB ' \&# '
 conversion flag characters removed, and referencing a NULL string.
 .PP
-If no format strings are specified, the default display is equivalent
-to specifying the
-.B \-x
-option.
+If no format strings are specified, the default display is very simular to the
+\fB\-x\fR
+output format (the \fB\-x\fR uses more space between format units than the default output).
 .SH "EXIT STATUS"
 .B hexdump
 exits 0 on success and >0 if an error occurred.