fix #12262: use the C dependency scanner also for ASM files

Files for the ASM language are those assembler files which are processed
by the C/CXX compiler, and they may contain preprocessor directives, so
run the C dependency scanner also on them.

Alex

Source/cmLocalUnixMakefileGenerator3.cxx

@@ -1559,7 +1559,7 @@ cmLocalUnixMakefileGenerator3
 
     // Create the scanner for this language
     cmDepends *scanner = 0;
-    if(lang == "C" || lang == "CXX" || lang == "RC")
+    if(lang == "C" || lang == "CXX" || lang == "RC" || lang == "ASM")
       {
       // TODO: Handle RC (resource files) dependencies correctly.
       scanner = new cmDependsC(this, targetDir, lang.c_str(), &validDeps);