Ignore dotfiles in lookup_srcs (#1218)

This makes the find and fd cases match, as fd already ignores dotfiles.

common.mk

@@ -66,7 +66,7 @@ include $(base_dir)/tools/torture.mk
 # Returns a list of files in directory $1 with file extension $2.
 # If available, use 'fd' to find the list of files, which is faster than 'find'.
 ifeq ($(shell which fd 2> /dev/null),)
-	lookup_srcs = $(shell find -L $(1)/ -name target -prune -o -iname "*.$(2)" -print 2> /dev/null)
+	lookup_srcs = $(shell find -L $(1)/ -name target -prune -o \( -iname "*.$(2)" ! -iname ".*" \) -print 2> /dev/null)
 else
 	lookup_srcs = $(shell fd -L ".*\.$(2)" $(1))
 endif