Fix %check section switch

Fix %check section switch

Using '%define %check exit 0' is an error since it redefines the rpm section
name as a macro.

This leads to including the contents of %check section into previously defined
section (e.g. %install) and therefore not only it breaks the build script in
the middle of execution by injecting 'exit 0', but also prevents
%__spec_install_post from running. This forbids execution of rpm post-scripts
which generate debug info, locale information, cleans up install dir and so on.

Setting up %__spec_check_pre variable will only disable the %check section.

Change-Id: Ifb6a847e298416c702409759457cdc03d0d563e2
Signed-off-by: Slava Barinov <v.barinov@samsung.com>