[driver] NuttX keyboard fixed to recognize special keys from event type

[ppisa]

This is initial fix to support both special keys and alphanumeric keys
in the Microwindows demo edit widgets.

This does not solve still application of the shift and capslock through modifiers.

Related NuttX problems with omitted delivery of special keys as KBD_SPECPRESS
and KBD_SPECREL for multiple keyboards is tracked at

apache/nuttx#19527

[ppisa]

@Acfboy please, look at my changes and test them.

By the way, it seems that

HAVE_FNT_SUPPORT = Y

has to be provided at least by nuttx-apps/graphics/microwindows/Makefile for correct build and linking. It probably can be omitted if it is removed from microwindows/src/include/mwconfig.nuttx. But we probably want to have it there for now.

probably the most flexible option would be to generate mwconfig fragment included through MWCONFIG_FILE at build time from NuttX Kconfig. But it would be too much complications for now.

[ghaerr]

Thank you @ppisa. Please let me know when you want this committed.

[Acfboy]

@Acfboy please, look at my changes and test them.

It looks good. I have tested them locally with apache/nuttx#19577, and I can type space and backspace in sim:mw now.

[ppisa]

Thanks to @Acfboy for testing. @ghaerr please push it to master. It is possible that there come more changes as the NuttX side is enhanced but I think that even this patch helps to move forward.