doc/nethack.6: Drop spurious request arguments

No *roff known to me interprets arguments to the `br` request.  They
don't complain, either, but some day that may change.

https://savannah.gnu.org/bugs/?61450

doc/nethack.6

@@ -36,7 +36,7 @@ nethack \- Exploring The Mazes of Menace
 .BR \-w | \-\-windowtype
 .I interface
 ]
-.br 1
+.br
 [
 .BI \-\-nethackrc: RC-file
 |
@@ -48,7 +48,7 @@ nethack \- Exploring The Mazes of Menace
 [
 .BR \-dec " | " \-ibm
 ]
-.br 1
+.br
 [
 .B \-u
 .I playername
@@ -106,7 +106,7 @@ Also
 [
 .B \-v
 ]
-.br 1
+.br
 [
 .B \-p
 .I profession
@@ -347,7 +347,7 @@ and the
 option can be used to skip any run-time configuration file.
 .PP
 .\" extra blank line
-.br 1
+.br
 .PP
 Some options provide feedback and then exit rather than play the game:
 .PP