Both iOS and tvOS need to have JIT disabled, so use the uikit qmake
scope for that. This was already done for PCRE 1, but the corresponding
change was lost for PCRE 2 (probably due to a bad merge).

Change-Id: Iac7997880c13b34ced46c63b748980c6fb700a0f
Task-number: QTBUG-62993
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Jake Petroules <jake.petroules@qt.io>