CMake: Fix WrapOpenSSL package

Since f19ce3898e0257dac1112754b1a84c24486bda01 we link OpenSSL to
QTlsBackendOpenSSLPlugin instead of QtNetwork itself.  In dependent Qt
repositories this leads to the following situation:

QTlsBackendOpenSSLPlugin's dependencies call
find_dependency(WrapOpenSSLHeaders), and OpenSSL_FOUND is set to ON in
that scope.  Later, we call find_package(WrapOpenSSL) in a different
scope.  find_package(WrapOpenSSLHeaders) bails out early, because the
target WrapOpenSSLHeaders::WrapOpenSSLHeaders exists.
find_package(OpenSSL) is not called again.  The check for OpenSSL_FOUND
fails, because the variable is not visible in the scope of
FindWrapOpenSSL.cmake, and we don't create the WrapOpenSSL::WrapOpenSSL
target.

Fix this by checking for the existence of the target OpenSSL::SSL
instead of the OpenSSL_FOUND variable.

Pick-to: 6.2 6.3
Fixes: QTBUG-99623
Change-Id: Idd0e8a60fabd0c7772413d557442c0012b0b436c
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>

0 files changed, 0 insertions, 0 deletions