kbuild: docbook: sync with Linux Kernel v3.15-rc1

This commit imports DocBook-related updates
from v3.14 to v3.15-rc1.

 - commit ec3fadd64b9940baa2a369bf978e8561837db3f5
    kbuild: docbook: use $(obj) and $(src) rather than specific path
 - commit 100da4c0150c97ce34d4d3b38bf2f5449b05ae4f
    kbuild: docbook: specify KERNELDOC dependency correctly
 - commit 6f89b9c1d6b29eaa600ac4a8ac1314b0d06f15e3
    kbuild: docbook: include cmd files more simply
 - commit ac6d662a95a6989d83b259ccf8ec01dd7903af73
    doc: Add "*.svg" to DocBook/.gitignore
 - commit 832919bfcf0cfd75767c68b0c61f7cf48be860a8
    DocBook: Make mandocs parallel-safe
 - commit c4d79a4799719f2b0cd354ee498aad605730c97e
    work around xmlto bug in htmldocs

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/doc/DocBook/.gitignore b/doc/DocBook/.gitignore
index 720f245..7ebd546 100644
--- a/doc/DocBook/.gitignore
+++ b/doc/DocBook/.gitignore
@@ -10,5 +10,6 @@
 *.out
 *.png
 *.gif
+*.svg
 media-indices.tmpl
 media-entities.tmpl
diff --git a/doc/DocBook/Makefile b/doc/DocBook/Makefile
index 9b4a9b6..593237f 100644
--- a/doc/DocBook/Makefile
+++ b/doc/DocBook/Makefile
@@ -26,6 +26,7 @@
 # The targets that may be used.
 PHONY += xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs cleandocs
 
+targets += $(DOCBOOKS)
 BOOKS := $(addprefix $(obj)/,$(DOCBOOKS))
 xmldocs: $(BOOKS)
 sgmldocs: xmldocs
@@ -44,17 +45,18 @@
 
 MAN := $(patsubst %.xml, %.9, $(BOOKS))
 mandocs: $(MAN)
+	$(if $(wildcard $(obj)/man/*.9),gzip -f $(obj)/man/*.9)
 
 installmandocs: mandocs
 	mkdir -p /usr/local/man/man9/
-	install doc/DocBook/man/*.9.gz /usr/local/man/man9/
+	install $(obj)/man/*.9.gz /usr/local/man/man9/
 
 ###
 #External programs used
 KERNELDOC = $(srctree)/scripts/kernel-doc
 DOCPROC   = $(objtree)/scripts/docproc
 
-XMLTOFLAGS = -m $(srctree)/doc/DocBook/stylesheet.xsl
+XMLTOFLAGS = -m $(srctree)/$(src)/stylesheet.xsl
 XMLTOFLAGS += --skip-validation
 
 ###
@@ -76,21 +78,9 @@
         ) > $(dir $@).$(notdir $@).cmd
 endef
 
-%.xml: %.tmpl FORCE
+%.xml: %.tmpl $(KERNELDOC) $(DOCPROC) FORCE
 	$(call if_changed_rule,docproc)
 
-###
-#Read in all saved dependency files
-cmd_files := $(wildcard $(foreach f,$(BOOKS),$(dir $(f)).$(notdir $(f)).cmd))
-
-ifneq ($(cmd_files),)
-  include $(cmd_files)
-endif
-
-###
-# Changes in kernel-doc force a rebuild of all documentation
-$(BOOKS): $(KERNELDOC)
-
 # Tell kbuild to always build the programs
 always := $(hostprogs-y)
 
@@ -128,16 +118,16 @@
 
 
 index = index.html
-main_idx = doc/DocBook/$(index)
+main_idx = $(obj)/$(index)
 build_main_index = rm -rf $(main_idx); \
 		   echo '<h1>U-Boot Bootloader HTML Documentation</h1>' >> $(main_idx) && \
 		   echo '<h2>U-Boot Version: $(UBOOTVERSION)</h2>' >> $(main_idx) && \
 		   cat $(HTML) >> $(main_idx)
 
 quiet_cmd_db2html = HTML    $@
-      cmd_db2html = xmlto xhtml $(XMLTOFLAGS) -o $(patsubst %.html,%,$@) $< && \
+      cmd_db2html = xmlto html $(XMLTOFLAGS) -o $(patsubst %.html,%,$@) $< && \
 		echo '<a HREF="$(patsubst %.html,%,$(notdir $@))/index.html"> \
-        $(patsubst %.html,%,$(notdir $@))</a><p>' > $@
+		$(patsubst %.html,%,$(notdir $@))</a><p>' > $@
 
 %.html:	%.xml
 	@(which xmlto > /dev/null 2>&1) || \
@@ -149,7 +139,7 @@
             cp $(PNG-$(basename $(notdir $@))) $(patsubst %.html,%,$@); fi
 
 quiet_cmd_db2man = MAN     $@
-      cmd_db2man = if grep -q refentry $<; then xmlto man $(XMLTOFLAGS) -o $(obj)/man $< ; gzip -f $(obj)/man/*.9; fi
+      cmd_db2man = if grep -q refentry $<; then xmlto man $(XMLTOFLAGS) -o $(obj)/man $< ; fi
 %.9 : %.xml
 	@(which xmlto > /dev/null 2>&1) || \
 	 (echo "*** You need to install xmlto ***"; \