1. A bogus address calculation was done (spotted by G. Smith).
2. The displayID was added to the data escape character even if the connection
type does not support multiple displays (spotted by G. Smith).
3. When calculation if data escape is necessary, the character 0xff could not
be escaped. Changed an updates all connection types (M. Dolze).
backlight handling:
Previously if keypad=yes was configured in LCDd.conf a value for the
backlight was sent, regardless of the configuration in hd44780-serial.c.
Now it decides upon the backlight flag from that file (enabling it in
LCDd.conf is still required). If the backlight flag indicates the device
supports backlight, the backlight_on / backlight_off values are sent (even
if they are 0x00)!
* Do not include system headers in shared files (stdlib.h).
* Don't include lcd.h only once in each driver.
* Remove some unnecessary headers from driver (e.g. syslog.h)
* Include <poll.h> instead of <sys/poll.h>
* Spelling fixes.
mmdolze