[xen master] xen/build: silence make warnings about missing auto.conf*

[patchbot@xxxxxxx]

commit 8d4c17a90b0a9b3d82628461090a54a2c7897154
Author:     Anthony PERARD <anthony.perard@xxxxxxxxxx>
AuthorDate: Mon Apr 27 09:31:13 2020 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Apr 27 09:31:13 2020 +0200

    xen/build: silence make warnings about missing auto.conf*
    
    In a clean tree, both files include/config/auto.conf{,.cmd} are
    missing and older version of GNU Make complain about it:
        Makefile:103: include/config/auto.conf: No such file or directory
        Makefile:106: include/config/auto.conf.cmd: No such file or directory
    
    Those warnings are harmless, make will create the files and start over. But
    to avoid confusion, we'll use "-include" to silence the warning.
    
    Those warning started to appear with commit 6c122d3984a5 ("xen/build:
    include include/config/auto.conf in main Makefile").
    
    Reported-by: Jan Beulich <jbeulich@xxxxxxxx>
    Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
    Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/xen/Makefile b/xen/Makefile
index 07f8ef8087..2b1dacb497 100644
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -150,10 +150,10 @@ config: FORCE
 else # !config-build
 
 ifeq ($(need-config),y)
-include include/config/auto.conf
+-include include/config/auto.conf
 # Read in dependencies to all Kconfig* files, make sure to run syncconfig if
 # changes are detected.
-include include/config/auto.conf.cmd
+-include include/config/auto.conf.cmd
 
 # Allow people to just run `make` as before and not force them to configure
 $(KCONFIG_CONFIG):
--
generated by git-patchbot for /home/xen/git/xen.git#master