[source] kernel: do not try to probe builtin modules on empty kmod package install

[LEDE Commits]

jogo pushed a commit to source.git, branch master:
https://git.lede-project.org/34c01e68b5d6b06ce3794ef0e2b06e81ec3ce8ca

commit 34c01e68b5d6b06ce3794ef0e2b06e81ec3ce8ca
Author: Jonas Gorski <jonas.gorski at gmail.com>
AuthorDate: Sun Jun 18 17:40:01 2017 +0200

    kernel: do not try to probe builtin modules on empty kmod package install
    
    Builtin modules are always present, and trying to load them will cause
    modprobe to spew errors when installing the empty kmod packages.
    
    Fix this by never generating any postinst module install instructions
    for builtin modules.
    
    Fixes #842.
    
    Signed-off-by: Jonas Gorski <jonas.gorski at gmail.com>
---
 include/kernel.mk | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/kernel.mk b/include/kernel.mk
index 7674f0d..d780ef0 100644
--- a/include/kernel.mk
+++ b/include/kernel.mk
@@ -136,6 +136,7 @@ define ModuleAutoLoad
 		local mod; \
 		shift 2; \
 		for mod in $$$$$$$$mods; do \
+			[ -e $(2)/$(MODULES_SUBDIR)/$$$$$$$$mod.ko ] || continue; \
 			mkdir -p $(2)/etc/modules.d; \
 			echo "$$$$$$$$mod" >> $(2)/etc/modules.d/$(1); \
 		done; \
@@ -154,6 +155,7 @@ define ModuleAutoLoad
 		local mod; \
 		shift 3; \
 		for mod in $$$$$$$$mods; do \
+			[ -e $(2)/$(MODULES_SUBDIR)/$$$$$$$$mod.ko ] || continue; \
 			mkdir -p $(2)/etc/modules.d; \
 			echo "$$$$$$$$mod" >> $(2)/etc/modules.d/$$$$$$$$priority-$(1); \
 		done; \