ACPI: ibm-acpi: fix Kconfig entries for ibm-acpi bay and dock
Support for ACPI_BAY has not been merged in mainline yet. Usage of
"depends on FOO=n" fails if FOO is undefined, thus ibm-acpi support
for bay was being made non-available in a kernel that has no other
sort of bay support.
Fix it to use "depends on ! FOO" instead, that does the right thing
when FOO is undefined. Fix ACPI_IBM_DOCK accordingly as well while
at it, and also improve the help text.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>