uml: fix symlink loops

symlinks to directories in the non-O= case were lacking -n, which meant
that, when the link already existed, a new link pointing at itself was
created in the target directory.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/um/Makefile

@@ -168,7 +168,7 @@ ifneq ($(KBUILD_SRC),)
 	$(Q)mkdir -p $(objtree)/include/asm-um
 	$(Q)ln -fsn $(srctree)/include/asm-$(HEADER_ARCH) include/asm-um/arch
 else
-	$(Q)cd $(TOPDIR)/include/asm-um && ln -sf ../asm-$(HEADER_ARCH) arch
+	$(Q)cd $(TOPDIR)/include/asm-um && ln -fsn ../asm-$(SUBARCH) arch
 endif
 
 $(objtree)/$(ARCH_DIR)/include:
@@ -180,7 +180,7 @@ $(ARCH_DIR)/include/sysdep: $(objtree)/$(ARCH_DIR)/include
 ifneq ($(KBUILD_SRC),)
 	$(Q)ln -fsn $(srctree)/$(ARCH_DIR)/include/sysdep-$(SUBARCH) $(ARCH_DIR)/include/sysdep
 else
-	$(Q)cd $(ARCH_DIR)/include && ln -sf sysdep-$(SUBARCH) sysdep
+	$(Q)cd $(ARCH_DIR)/include && ln -fsn sysdep-$(SUBARCH) sysdep
 endif
 
 $(ARCH_DIR)/os:
@@ -188,7 +188,7 @@ $(ARCH_DIR)/os:
 ifneq ($(KBUILD_SRC),)
 	$(Q)ln -fsn $(srctree)/$(ARCH_DIR)/os-$(OS) $(ARCH_DIR)/os
 else
-	$(Q)cd $(ARCH_DIR) && ln -sf os-$(OS) os
+	$(Q)cd $(ARCH_DIR) && ln -fsn os-$(OS) os
 endif
 
 # Generated files