i2c-stub: Move to drivers/i2c

Move the i2c-stub driver to drivers/i2c, to match the Kconfig entry.
This is less confusing that way.

I also fixed all checkpatch warnings and errors.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Peter Huewe <peterhuewe@gmx.de>
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index beee6b2..1722f50 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -8,6 +8,7 @@
 obj-$(CONFIG_I2C_CHARDEV)	+= i2c-dev.o
 obj-$(CONFIG_I2C_MUX)		+= i2c-mux.o
 obj-y				+= algos/ busses/ muxes/
+obj-$(CONFIG_I2C_STUB)		+= i2c-stub.o
 
 ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG
 CFLAGS_i2c-core.o := -Wno-deprecated-declarations