Temporarily relax the dlopen flag.

On MacOSX, with the local flag the 'Module' used by cling is missing quite
a few symbols:

root [0] int a = 2;
root [1] a
ExecutionContext: use of undefined symbol '_ZN5cling16ValuePrinterInfoC1EPN5clang4ExprEPNS1_10ASTContextE'!
ExecutionContext: use of undefined symbol '_ZN5cling20valuePrinterInternal13flushToStreamERN4llvm11raw_ostreamERKSs'!
ExecutionContext: use of undefined symbol '_ZN5cling20valuePrinterInternal18printValue_DefaultEPKvRKNS_16ValuePrinterInfoE'!
ExecutionContext: use of undefined symbol '_ZN5cling20valuePrinterInternal17printType_DefaultERKNS_16ValuePrinterInfoE'!
ExecutionContext::executeFunction: symbol '_ZN5cling16ValuePrinterInfoC1EPN5clang4ExprEPNS1_10ASTContextE' unresolved while linking function '_Z15__cling_Un1Qu31v'!
ExecutionContext::executeFunction: symbol '_ZN5cling20valuePrinterInternal13flushToStreamERN4llvm11raw_ostreamERKSs' unresolved while linking function '_Z15__cling_Un1Qu31v'!
ExecutionContext::executeFunction: symbol '_ZN5cling20valuePrinterInternal17printType_DefaultERKNS_16ValuePrinterInfoE' unresolved while linking function '_Z15__cling_Un1Qu31v'!
ExecutionContext::executeFunction: symbol '_ZN5cling20valuePrinterInternal18printValue_DefaultEPKvRKNS_16ValuePrinterInfoE' unresolved while linking function '_Z15__cling_Un1Qu31v'!
root [2] .q