Fix build breakage with cmake 2.8
Fix build breakage with cmake 2.8

Change-Id: Ida32c782f6e7bf09bb3f16447be9092c15854986
Reviewed-on: http://review.couchbase.org/42542
Tested-by: Mark Nunberg <e7d42768707bf23038325b0b68d4b577e5f6064a@haskalah.org>
Reviewed-by: Sergey Avseyev <87f6d5e4fd3644c3c20800cde7fd3ad1569370b3@gmail.com>

couchbase/libcouchbase,senthilkumaranb/libcouchbase,mnunberg/libcouchbase,kojiromike/libcouchbase,mody/libcouchbase,couchbase/libcouchbase,senthilkumaranb/libcouchbase,mody/libcouchbase,couchbase/libcouchbase,mnunberg/libcouchbase,maxim-ky/libcouchbase,avsej/libcouchbase,mody/libcouchbase,maxim-ky/libcouchbase,couchbase/libcouchbase,PureSwift/libcouchbase,signmotion/libcouchbase,couchbase/libcouchbase,mnunberg/libcouchbase,maxim-ky/libcouchbase,couchbase/libcouchbase,PureSwift/libcouchbase,maxim-ky/libcouchbase,signmotion/libcouchbase,kojiromike/libcouchbase,PureSwift/libcouchbase,couchbase/libcouchbase,avsej/libcouchbase,signmotion/libcouchbase,mody/libcouchbase,avsej/libcouchbase,kojiromike/libcouchbase,avsej/libcouchbase,senthilkumaranb/libcouchbase,signmotion/libcouchbase,mnunberg/libcouchbase,PureSwift/libcouchbase,avsej/libcouchbase,avsej/libcouchbase,avsej/libcouchbase,senthilkumaranb/libcouchbase,kojiromike/libcouchbase,mnunberg/libcouchbase