staging/easycap: make module params private/static, fix build

staging/easycap: make module params private/static, fix build

The easycap driver has module parameters (bars, gain, & debug)
with global scope that intrude on the kernel namespace and cause
build problems.  Change the names of them to be driver-specific
and make 2 of them static.

drivers/built-in.o:(.bss+0x97c00): multiple definition of `debug'
ld: Warning: size of symbol `debug' changed from 58 in arch/x86/built-in.o to 4 in drivers/built-in.o

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Mike Thomas <rmthomas@sciolus.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>