[lldb][Commands][NFC] image lookup: remove unused local variable (#146554)

The `current_module` pointer here was never set, but we check it when
looping over the `target_modules` list. Presumably the intention was to
avoid calling `LookupInModule` if we already found the type in the
current module. This patch removes this `current_module`. If we decide
the output below is not what the user should see, we can revisit the
implementation.

Current output:
```
(lldb) im loo -vt Foo --all
Best match found in /Users/jonas/Git/llvm-worktrees/llvm-project/a.out:
id = {0x00000037}, name = "Foo", byte-size = 1, decl = foo.cpp:1, compiler_type = "struct Foo {
}"

1 match found in /Users/jonas/Git/llvm-worktrees/llvm-project/a.out:
id = {0x00000037}, name = "Foo", byte-size = 1, decl = foo.cpp:1, compiler_type = "struct Foo {
}"
```
which seems fine.

Note, there can be multiple matches *within* the current module, so if
we did the naive thing of skipping the `current_module` when printing
with `--all`, then we would miss some matches.

Author: Michael137

lldb/source/Commands/CommandObjectTarget.cpp

@@ -4086,8 +4086,6 @@ class CommandObjectTargetModulesLookup : public CommandObjectParsed {
     // Dump all sections for all modules images
 
     if (command.GetArgumentCount() == 0) {
-      ModuleSP current_module;
-
       // Where it is possible to look in the current symbol context first,
       // try that.  If this search was successful and --all was not passed,
       // don't print anything else.
@@ -4110,8 +4108,7 @@ class CommandObjectTargetModulesLookup : public CommandObjectParsed {
       }
 
       for (ModuleSP module_sp : target_modules.ModulesNoLocking()) {
-        if (module_sp != current_module &&
-            LookupInModule(m_interpreter, module_sp.get(), result,
+        if (LookupInModule(m_interpreter, module_sp.get(), result,
                            syntax_error)) {
           result.GetOutputStream().EOL();
           num_successful_lookups++;