musl: add missing submodule auto-initialization

Signed-off-by: Florian Hofhammer <florian.hofhammer@fhofhammer.de>

Author: florianhofhammer

Makefile.in

@@ -252,6 +252,12 @@ else
 GLIBC_SRC_GIT :=
 endif
 
+ifeq ($(findstring $(srcdir),$(MUSL_SRCDIR)),$(srcdir))
+MUSL_SRC_GIT := $(MUSL_SRCDIR)/.git
+else
+MUSL_SRC_GIT :=
+endif
+
 ifeq ($(findstring $(srcdir),$(QEMU_SRCDIR)),$(srcdir))
 QEMU_SRC_GIT := $(QEMU_SRCDIR)/.git
 else
@@ -742,7 +748,7 @@ stamps/build-gcc-musl-stage1: $(GCC_SRCDIR) $(GCC_SRC_GIT) stamps/build-binutils
 	$(MAKE) -C $(notdir $@) inhibit-libc=true install-target-libgcc
 	mkdir -p $(dir $@) && touch $@
 
-stamps/build-musl-linux-headers: $(MUSL_SRCDIR) stamps/build-gcc-musl-stage1
+stamps/build-musl-linux-headers: $(MUSL_SRCDIR) $(MUSL_SRC_GIT) stamps/build-gcc-musl-stage1
 	rm -rf $@ $(notdir $@)
 	mkdir $(notdir $@)
 	cd $(notdir $@) && CC="$(MUSL_CC_FOR_TARGET)" $</configure \
@@ -755,7 +761,7 @@ stamps/build-musl-linux-headers: $(MUSL_SRCDIR) stamps/build-gcc-musl-stage1
 	$(MAKE) -C $(notdir $@) install-headers
 	mkdir -p $(dir $@) && touch $@
 
-stamps/build-musl-linux: $(MUSL_SRCDIR) stamps/build-gcc-musl-stage1
+stamps/build-musl-linux: $(MUSL_SRCDIR) $(MUSL_SRC_GIT) stamps/build-gcc-musl-stage1
 	rm -rf $@ $(notdir $@)
 	mkdir $(notdir $@)
 	cd $(notdir $@) && \