Don't explicitly mention SOONG_CONFIG_ variables

The soong config variables should be controlled via
$(call soong_config_set/get) instead of using the
underlaying variable. Update the comments in the
auto generated makefiles to reflect that.

Bug: 220940864
Test: m mainline_modules_sdks_test && /ssd/aosp-master/out/host/linux-x86/nativetest64/mainline_modules_sdks_test/mainline_modules_sdks_test
Change-Id: I8907d89ceb12e0a1e9ce53220a784e4a69502687

build/mainline_modules_sdks.py

@@ -134,7 +134,7 @@ class SoongConfigBoilerplateInserter(FileTransformation):
                 namespace = self.configVar.namespace
                 name = self.configVar.name
                 module_content.append(f"""\
-    // Do not prefer prebuilt if SOONG_CONFIG_{namespace}_{name} is true.
+    // Do not prefer prebuilt if the Soong config variable "{name}" in namespace "{namespace}" is true.
     prefer: true,
     soong_config_variables: {{
         {name}: {{