perf Documentation: Fix out-of-tree asciidoctor man page generation

The dependency for the man page rule using asciidoctor incorrectly
specifies a source file in $(OUTPUT).  When building out-of-tree, the
source file is not found, resulting in a fall-back to the following rule
which uses xmlto.

Signed-off-by: Ben Hutchings <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Fixes: ffef80e ("perf Documentation: Support for asciidoctor")
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

tools/perf/Documentation/Makefile

@@ -280,7 +280,7 @@ $(MAN_HTML): $(OUTPUT)%.html : %.txt
 	mv $@+ $@
 
 ifdef USE_ASCIIDOCTOR
-$(OUTPUT)%.1 $(OUTPUT)%.5 $(OUTPUT)%.7 : $(OUTPUT)%.txt
+$(OUTPUT)%.1 $(OUTPUT)%.5 $(OUTPUT)%.7 : %.txt
 	$(QUIET_ASCIIDOC)$(RM) $@+ $@ && \
 	$(ASCIIDOC) -b manpage -d manpage \
 		$(ASCIIDOC_EXTRA) -aperf_version=$(PERF_VERSION) -o $@+ $< && \