https://github.com/libofx/libofx/commit/ee296908c23a944b9b034c9b1f8b974edcb44b80

From ee296908c23a944b9b034c9b1f8b974edcb44b80 Mon Sep 17 00:00:00 2001
From: Sam James <sam@gentoo.org>
Date: Sat, 6 Mar 2021 06:09:11 +0000
Subject: [PATCH] Makefile.am, doc/Makefile.am: don't override docdir

'docdir' is already provided by autotools. By not overriding it,
we allow the directory to be easily overriden at build time.

By default, docdir is /usr/share/doc/libofx, so no change!

e.g. In Gentoo, we prefer to use --docdir=/usr/share/doc/${PF}
where ${PF} represents the upstream version combined with any
internal distribution changes made.

Signed-off-by: Sam James <sam@gentoo.org>
--- a/Makefile.am
+++ b/Makefile.am
@@ -6,8 +6,6 @@ endif
 DIST_SUBDIRS = m4 inc dtd lib doc . ofx2qif ofxdump ofxconnect
 SUBDIRS = m4 inc dtd lib doc . ofx2qif ofxdump $(MAYBE_OFXCONNECT)
 
-docdir = $(datadir)/doc/libofx
-
 doc_DATA = \
   AUTHORS \
   COPYING \
diff --git a/doc/Makefile.am b/doc/Makefile.am
index 23e9d34..bd0a04d 100644
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -1,7 +1,5 @@
 SUBDIRS =
 
-docdir = ${prefix}/share/doc/libofx
-
 EXTRA_DIST = \
 	doxygen.cfg \
 	ofx_sample_files \