ivi-shell: fix minor typos

- ivi-shell/hmi-controller.c:41: a to an
- ivi-shell/hmi-controller.c:1296: Duplicated 'a'
- ivi-shell/ivi-layout-export.h:28: An to A

Signed-off-by: Abdur Rehman <arehmanq199@gmail.com>
Reviewed-by: Yong Bakos <ybakos@humanoriented.com>
2 files changed