run_scaled: fix manpage (--scale, not --scaling)

The run_scaled script supports an argument called --scale, but the
manpage specifies --scaling for some reason. Fix the occurences to match
the implementation.

fs/share/man/man1/run_scaled.1

@@ -14,7 +14,7 @@ run_scaled - run an X11 application upscaled or downscaled
 .PD 0
 .HP \w'run_scaled\ 'u
 \fBrun_scaled\fP
-[\fB--scaling\fP=\fIVALUE\fP] application [application-arguments]\fB
+[\fB--scale\fP=\fIVALUE\fP] application [application-arguments]\fB
 .PD
 
 .\" --------------------------------------------------------------------
@@ -30,7 +30,7 @@ Starts the command "\fBxterm -ls\fP", with the default scaling of \fB2\fP.
 .br
 The xterm window will be twice as big as it normally would be.
 .TP
-\fBrun_scaled --scaling=250% firefox\fP
+\fBrun_scaled --scale=250% firefox\fP
 Start firefox, upscaled by 250%.
 .TP
 \fBrun_scaled --xpra-arg=--speaker=off --xpra-arg=--microphone=off wine notepad.exe\fP
@@ -40,7 +40,7 @@ Starts the command "\fBwine notepad.exe\fP", with audio inputs and outputs disab
 .SH OPTIONS
 
 .TP
-\fB--scaling\fP=\fIVALUE\fP
+\fB--scale\fP=\fIVALUE\fP
 The scaling factor to apply, specified as:
 .RS
 .IP \fBnumber\fP