Include .td and .txt files in the greps.  This will allow me to find symbols in
them, and also count them in the LOC of LLVM for the nightly tester.

llvm-svn: 15786
diff --git a/llvm/utils/llvmgrep b/llvm/utils/llvmgrep
index 5ed48f1..0b3553e 100755
--- a/llvm/utils/llvmgrep
+++ b/llvm/utils/llvmgrep
@@ -7,7 +7,7 @@
   cd $TOPDIR
   find docs include lib tools utils projects -type f \
       \( -path '*/doxygen/*' -o -path '*/Burg/*' \) -prune -o \
-      -name '*.[cdhyl]*' \
+      -name '*.[cdhylt]*' \
       \! -name '*~' \
       \! -name '#*' \
       \! -name '*.ll' \