Move checking for I2C headers to configure.in. Check for FreeBSD's iic

headers as well.

TODO

@@ -7,7 +7,6 @@ Please send a message to the mailing list if you have any question.
 Things for the short term:
 - Use centralized command message parsing engine (more secure)
 - more features for existing display drivers (e.g. adapt them to bignum library)
-- documentation (any help is appreciated)
 - lcd_lib: Make use of the options parameter to specify SEAMLESS_HBARS, the
   height of hbars, etc.
 - lcterm: Support keyboard input

acinclude.m4

@@ -202,10 +202,9 @@ dnl			else
 				HD44780_DRIVERS="$HD44780_DRIVERS hd44780-hd44780-ethlcd.o"
 				AC_DEFINE(WITH_ETHLCD,[1],[Define to 1 if you want to build hd44780 driver with ethlcd support])
 			fi
-			AC_CHECK_HEADER(linux/i2c-dev.h,
+			if test "$x_ac_have_i2c" = yes; then
 				HD44780_DRIVERS="$HD44780_DRIVERS hd44780-hd44780-i2c.o"
-				AC_DEFINE(HAVE_I2C,[1],[Define to 1 if you have the i2c headers])
-			)
+			fi
 			DRIVERS="$DRIVERS hd44780${SO}"
 			actdrivers=["$actdrivers hd44780"]
 			;;

configure.in

@@ -160,6 +160,12 @@ else
 	AC_MSG_WARN([Can't talk to the parallel port, disabling drivers that use it.])
 fi
 
+x_ac_have_i2c=no
+AC_CHECK_HEADERS([linux/i2c-dev.h dev/iicbus/iic.h], [x_ac_have_i2c=yes])
+if test "$x_ac_have_i2c" = yes; then
+	AC_DEFINE(HAVE_I2C,[1],[Define to 1 if you have the i2c headers])
+fi
+
 dnl Checks for header files.
 AC_HEADER_DIRENT
 AC_HEADER_STDC