qemu-char: don't issue CHR_EVENT_OPEN in a BH

commit: bd5c51ee6c4f1c79cae5ad2516d711a27b4ea8ec

Signed-off-by: Romain Naour <romain.naour@openwide.fr>
doc: add gnmouse help

Signed-off-by: Romain Naour <romain.naour@openwide.fr>
gnmouse: fix typo

Signed-off-by: Romain Naour <romain.naour@openwide.fr>