Make rdfind optional

A number of distributions don't include rdfind by default.  This is an
optimization, so make it optional via a --ignore-duplicates option and a
new make target.

Distributions that include rdfind should add it as a dependency for
their linux-firmware package.  Those that don't should use the new
target or option.

Signed-off-by: Josh Boyer <jwboyer@kernel.org>

Makefile

@@ -30,6 +30,10 @@ install:
 	install -d $(DESTDIR)$(FIRMWAREDIR)
 	./copy-firmware.sh $(DESTDIR)$(FIRMWAREDIR)
 
+install-nodedup:
+	install -d $(DESTDIR)$(FIRMWAREDIR)
+	./copy-firmware.sh --ignore-duplicates $(DESTDIR)$(FIRMWAREDIR)
+
 install-xz:
 	install -d $(DESTDIR)$(FIRMWAREDIR)
 	./copy-firmware.sh --xz $(DESTDIR)$(FIRMWAREDIR)

copy-firmware.sh

@@ -9,6 +9,7 @@ prune=no
 # shellcheck disable=SC2209
 compress=cat
 compext=
+skip_dedup=0
 
 while test $# -gt 0; do
     case $1 in
@@ -44,6 +45,11 @@ while test $# -gt 0; do
             shift
             ;;
 
+        --ignore-duplicates)
+            skip_dedup=1
+            shift
+            ;;
+
         -*)
             if test "$compress" = "cat"; then
                 echo "ERROR: unknown command-line option: $1"
@@ -70,9 +76,11 @@ if [ -z "$destdir" ]; then
 fi
 
 if ! command -v rdfind >/dev/null; then
-	echo "ERROR: rdfind is not installed"
+	if [ "$skip_dedup" != 1 ]; then
+    		echo "ERROR: rdfind is not installed.  Pass --ignore-duplicates to skip deduplication"
 		exit 1
 	fi
+fi
 
 # shellcheck disable=SC2162 # file/folder name can include escaped symbols
 grep -E '^(RawFile|File):' WHENCE | sed -E -e 's/^(RawFile|File): */\1 /;s/"//g' | while read k f; do
@@ -87,6 +95,7 @@ grep -E '^(RawFile|File):' WHENCE | sed -E -e 's/^(RawFile|File): */\1 /;s/"//g'
     fi
 done
 
+if [ "$skip_dedup" != 1 ] ; then
 	$verbose "Finding duplicate files"
 	rdfind -makesymlinks true -makeresultsfile false "$destdir" >/dev/null
 	find "$destdir" -type l | while read -r l; do
@@ -94,6 +103,7 @@ find "$destdir" -type l | while read -r l; do
 		$verbose "Correcting path for $l"
 		ln -fs "$(realpath --relative-to="$(dirname "$(realpath -s "$l")")" "$target")" "$l"
 	done
+fi
 
 # shellcheck disable=SC2162 # file/folder name can include escaped symbols
 grep -E '^Link:' WHENCE | sed -e 's/^Link: *//g;s/-> //g' | while read f d; do