When BUILD_DOCBOOK_HTML is NO, keep the rules, just omit the target

  (and similarly for PS and PDF)

The previous setup nuked the rules for making the documentation when
BUILD_DOCBOOK_HTML=NO.  This meant that "make html" didn't work.

There isn't any reason to nuke the rules (so far as Simon and I know).

1 files changed, 6 insertions, 20 deletions

diff --git a/rules/docbook.mk b/rules/docbook.mk
index 922574e577..080874d86a 100644
--- a/rules/docbook.mk
+++ b/rules/docbook.mk
@@ -26,6 +26,8 @@ $(call all-target,$1,)
 
 ifeq "$$(BUILD_DOCBOOK_HTML)" "YES"
 $(call all-target,$1,html_$1)
+INSTALL_HTML_DOC_DIRS += $1/$2
+endif
 
 html_$1 : $1/$2/index.html
 
@@ -42,16 +44,12 @@ $1/$2/index.html: $$($1_DOCBOOK_SOURCES)
 	cp mk/fptools.css $$(dir $$@)
 endif
 
-INSTALL_HTML_DOC_DIRS += $1/$2
-else
-html_$1 :
-	@echo "*** HTML documentation is disabled; BUILD_DOCBOOK_HTML = NO"
-	@exit 1
-endif
 
 .PHONY: ps_$1
 ifeq "$$(BUILD_DOCBOOK_PS)" "YES"
 $(call all-target,$1,ps_$1)
+INSTALL_DOCS += $1/$2.ps
+endif
 
 ps_$1 : $1/$2.ps
 
@@ -60,15 +58,10 @@ $1/$2.ps: $$($1_DOCBOOK_SOURCES)
 	"$$(DBLATEX)" $$(DBLATEX_OPTS) $1/$2.xml --ps -o $$@
 endif
 
-INSTALL_DOCS += $1/$2.ps
-else
-ps_$1 :
-	@echo "*** PS documentation is disabled; BUILD_DOCBOOK_PS = NO"
-	@exit 1
-endif
-
 ifeq "$$(BUILD_DOCBOOK_PDF)" "YES"
 $(call all-target,$1,pdf_$1)
+INSTALL_DOCS += $1/$2.pdf
+endif
 
 .PHONY: pdf_$1
 pdf_$1 : $1/$2.pdf
@@ -78,12 +71,5 @@ $1/$2.pdf: $$($1_DOCBOOK_SOURCES)
 	"$$(DBLATEX)" $$(DBLATEX_OPTS) $1/$2.xml --pdf -o $$@
 endif
 
-INSTALL_DOCS += $1/$2.pdf
-else
-pdf_$1 :
-	@echo "*** PDF documentation is disabled; BUILD_DOCBOOK_PDF = NO"
-	@exit 1
-endif
-
 endef