[lldb][yaml2macho-core] Set binary path for tests differently

The way I was setting the path to the yaml2macho-core tool for
API tests assumed that the llvm tool bin directory was the same
as the lldb tool bin directory.  There are build configuration
styles where they are not.  Set it the same way lldb-dap etc
are set to the lldb bin dir.

(cherry picked from commit 162b87b)

Author: jasonmolenda

lldb/packages/Python/lldbsuite/test/dotest.py

@@ -279,9 +279,6 @@ def parseOptionsAndInitTestdirs():
         configuration.llvm_tools_dir = args.llvm_tools_dir
         configuration.filecheck = shutil.which("FileCheck", path=args.llvm_tools_dir)
         configuration.yaml2obj = shutil.which("yaml2obj", path=args.llvm_tools_dir)
-        configuration.yaml2macho_core = shutil.which(
-            "yaml2macho-core", path=args.llvm_tools_dir
-        )
 
     if not configuration.get_filecheck_path():
         logging.warning("No valid FileCheck executable; some tests may fail...")
@@ -561,6 +558,8 @@ def setupSysPath():
     if is_exe(lldbDAPExec):
         os.environ["LLDBDAP_EXEC"] = lldbDAPExec
 
+    configuration.yaml2macho_core = shutil.which("yaml2macho-core", path=lldbDir)
+
     lldbPythonDir = None  # The directory that contains 'lldb/__init__.py'
 
     # If our lldb supports the -P option, use it to find the python path: