Port of BAS 2.4 to NuttX by Alan Carvalho de Assis
Resolve conflict
Merge remote-tracking branch 'origin/master' into bas24
Include unistd.h for execl()
Merge remote-tracking branch 'origin/master' into bas24
Add commits to BAS 2.4 Kconfig file
Update README files
Add BSD header to lib_istty.c
Merge remote-tracking branch 'origin/master' into bas24
Resolve conflict
More BAS 2.4 fixes
More compile fixes
Merge remote-tracking branch 'origin/master' into bas24
Fix some configuration dependencies, warnings, back up some previous changes that weren't really necessary
Merge remote-tracking branch 'origin/master' into bas24
Remove times() function because it doesn't exist on NuttX

Signed-off-by: Alan Carvalho de Assis <acassis@gmail.com>
Remove locale support because it is not supported on
 NuttX

Signed-off-by: Alan Carvalho de Assis <acassis@gmail.com>
Fix BAS 2.4 Makefile
SAM4: Fix a usbnsh build problem that has crept into all serial drivers
Fix a few more EFM32 integration bugs