V4L/DVB (4606): Add driver for TUA6100

This driver was originally in budget-av.c, however I have extracted it into
a seperate file to permit reuse.
I also reworked the code to make it maintainable. I then examined the KNC1
windows drivers and rewrote the code in order to configure the PLL as they
do. This solves a lot of reported tuning problems.

Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/dvb/frontends/Kconfig b/drivers/media/dvb/frontends/Kconfig
index 9e5ff0d..080fa25 100644
--- a/drivers/media/dvb/frontends/Kconfig
+++ b/drivers/media/dvb/frontends/Kconfig
@@ -296,4 +296,11 @@
 	help
 	  An SEC control chip.
 
+config DVB_TUA6100
+	tristate "TUA6100 PLL"
+	depends on DVB_CORE && I2C
+	default m if DVB_FE_CUSTOMISE
+	help
+	  A DVBS PLL chip.
+
 endmenu