patch 9.1.0119: can move away from cmdwin using win_splitmove()

patch 9.1.0119: can move away from cmdwin using win_splitmove()

Problem:  can switch windows while textlocked via f_win_gotoid and
          f_win_splitmove (which also allows switching in the cmdwin).
Solution: Check text_or_buf_locked in f_win_splitmove()
          (Sean Dewar)

While at it, call text_or_buf_locked() in f_win_gotoid() instead of
testing for cmdwin_type() (which text_buf_locked() does and
in addition will also verify that the buffer is not locked).

closes: #14042

Signed-off-by: Sean Dewar <6256228+seandewar@users.noreply.github.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>