cmake.bbclass: force CMAKE_INSTALL_SO_NO_EXE to be 0

cmake.bbclass: force CMAKE_INSTALL_SO_NO_EXE to be 0

By default cmake guesses whether install shared libaries with exec
permissions or not based on host distribution, so this behaviour
changes from host to host. OpenEmbedded assumes shared libraries to
be with exec permissions (reverse way brakes stripping, for example),
so let's force this in cmake configure invocation.

Signed-off-by: Roman I Khimov <khimov@altell.ru>
Acked-by: Ash Charles <ashcharles@gmail.com>
Acked-by: Khem Raj <raj.khem@gmail.com>