kconfig: Fix streamline_config to read multi line deps in Kconfig files

I noticed that some Kconfig files have multi line dependencies
that continue with a backslash. Those dependencies on the next
line will be missed by streamline_config.

For example:

config CS89x0
	tristate "CS89x0 support"
	depends on NET_ETHERNET && (ISA || EISA || MACH_IXDP2351 \
		|| ARCH_IXDP2X01 || MACH_MX31ADS)

The "|| ARCH_IXDP2X01 || MACH_MX31ADS)" will not be processed.

This patch adds code to handle this case.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>