man: move gbm-format from weston.ini(5) to weston-drm(7)

This option is used only with the DRM-backend. Options in weston.ini(5)
should be either generic or for backends that do not have their own man
page yet.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

man/weston-drm.man

@@ -43,6 +43,15 @@ section of
 .
 The DRM backend uses the following entries from
 .BR weston.ini .
+.SS Section core
+.TP
+\fBgbm-format\fR=\fIformat\fR
+sets the GBM format used for the framebuffer for the GBM backend. Can be
+.B xrgb8888,
+.B xrgb2101010,
+.B rgb565.
+By default, xrgb8888 is used.
+
 .SS Section output
 .TP
 \fBname\fR=\fIconnector\fR

man/weston.ini.man

@@ -148,16 +148,6 @@ target vertical blank, increasing output latency. The default value is 7
 milliseconds. The allowed range is from -10 to 1000 milliseconds. Using a
 negative value will force the compositor to always miss the target vblank.
 .TP 7
-.BI "gbm-format="format
-sets the GBM format used for the framebuffer for the GBM backend. Can be
-.B xrgb8888,
-.B xrgb2101010,
-.B rgb565.
-By default, xrgb8888 is used.
-.RS
-.PP
-.RE
-.TP 7
 .BI "idle-time="seconds
 sets Weston's idle timeout in seconds. This idle timeout is the time
 after which Weston will enter an "inactive" mode and screen will fade to