Force weak per-cpu definitions


Linux Kernel Configuration
└─>Kernel hacking
└─>Compile-time checks and compiler options
└─>Force weak per-cpu definitions
In linux kernel since version 2.6.32 (release Date: 2009-12-02)  
s390 and alpha require percpu variables in modules to be
defined weak to work around addressing range issue which
puts the following two restrictions on percpu variable

1. percpu symbols must be unique whether static or not
2. percpu variables can't be defined inside a function

To ensure that generic code follows the above rules, this
option forces all percpu variables to be defined as weak.