top: avoid premature forced loss of that bottom window

top: avoid premature forced loss of that bottom window

In the commit shown below the bottom window was forced
off if a full screen replacement function was invoked.
It did so by setting Frames_signal after calling those
routines from the keys_global function. However, there
was sometimes a possibility such action was premature.

At least two of those full screen replacement routines
may issue an error message & return without corrupting
the screen. As such, forcing off that bottom window is
totally unnecessary. It therefore should be preserved.

So this commit just moves the setting of Frames_signal
to the full screen replacement routines when possible.

Reference(s):
. May, 2022 - bottom window forced off for some
commit d66c1f39b52d53ec279fc638aa4a6352d7672201

Signed-off-by: Jim Warner <james.warner@comcast.net>