The internal variable 'gdb_actual_connections' is used by log and
by semihosting to determine if there are active GDB connections.
Keep the variable local in server's code and only export its value
through a dedicated function.
This solves the issue detected by 'parse' of the variable defined
as global but not declared in any include file.
Change-Id: I6e14f4cb1097787404094636f8a2a291340222dd
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/7673
Tested-by: jenkins