[NFC] Turn "load dependent files" boolean into an enum

This is an NFC commit to refactor the "load dependent files" parameter
from a boolean to an enum value. We want to be able to specify a
default, in which case we decide whether or not to load the dependent
files based on whether the target is an executable or not (i.e. a
dylib).

This is a dependency for D51934.

Differential revision: https://reviews.llvm.org/D51859

llvm-svn: 342633

lldb/source/Commands/CommandObjectProcess.cpp

@@ -459,7 +459,7 @@ protected:
       Status error;
 
       error = m_interpreter.GetDebugger().GetTargetList().CreateTarget(
-          m_interpreter.GetDebugger(), "", "", false,
+          m_interpreter.GetDebugger(), "", "", eLoadDependentsNo,
           nullptr, // No platform options
           new_target_sp);
       target = new_target_sp.get();