[openwrt/openwrt] tools/automake: do not delete libtool in clean targets

[LEDE Commits]

robimarko pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/30105c77efc09ec5edbaba4741f4f8f265f1f2aa

commit 30105c77efc09ec5edbaba4741f4f8f265f1f2aa
Author: Michael Pratt <mcpratt at pm.me>
AuthorDate: Sun Oct 6 04:23:10 2024 -0400

    tools/automake: do not delete libtool in clean targets
    
    For the building of some packages, it is helpful
    to completely clean the packaged release copy of the source,
    however this usually deletes libtool if used,
    otherwise causing the need to run the bootstrap script twice.
    
    Not deleting libtool allows compilation to continue directly
    after cleaning pre-generated files in the package distribution.
    
    Signed-off-by: Michael Pratt <mcpratt at pm.me>
    Link: https://github.com/openwrt/openwrt/pull/16522
    Signed-off-by: Robert Marko <robimarko at gmail.com>
---
 tools/automake/patches/999-clean-am.patch | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/automake/patches/999-clean-am.patch b/tools/automake/patches/999-clean-am.patch
index 87a0d6f3f6..a9642d1c79 100644
--- a/tools/automake/patches/999-clean-am.patch
+++ b/tools/automake/patches/999-clean-am.patch
@@ -18,3 +18,11 @@
  
  .PHONY: clean mostlyclean distclean maintainer-clean \
  clean-generic mostlyclean-generic distclean-generic maintainer-clean-generic
+--- a/lib/am/libtool.am
++++ b/lib/am/libtool.am
+@@ -25,4 +25,4 @@ clean-libtool:
+ 
+ ?TOPDIR_P?distclean-am: distclean-libtool
+ ?TOPDIR_P?distclean-libtool:
+-?TOPDIR_P?	-rm -f libtool config.lt
++?TOPDIR_P?	-touch libtool config.lt