ANDROID: GKI: core: Export for runqueues

    - Add EXPORT_SYMBOL_GPL for runqueues().

    - This API is required by loadable driver module,to get number of
    jobs in the run queue (state R) or waiting for disk I/O (state D)
    averaged over 1 min.

Signed-off-by: Abhilasha Rao <abhilasha.hv@samsung.corp-partner.google.com>
Bug: 158067689
Change-Id: I3e80a46bef2e7c92714b68cc5b6b617ac50bc478
(cherry picked from commit 6b0a9dc6df8d8be21c8d178a01e0711b0fe6ce73)