configure.ac: make GIR_DIR configurable

Some .gir files such as GLib-2.0.gir are arch related which contain such
as lengths of pointers that they are different for 64 and 32 bit target.
It causes install file conflicts for multilib when intall
gobject-introspection and lib32-gobject-introspection both.

Add configure option 'with-gir-dir-prefix' for autotools to make .gir
could be installed to a configured path such as ${libdir}. And update
girdir in .pc files as well.

Upstream-Status: Accepted [https://gitlab.gnome.org/GNOME/gobject-introspection/commit/3301c7e]

Signed-off-by: Kai Kang <kai.kang@windriver.com>
---
 configure.ac                              | 7 +++++--
 gobject-introspection-1.0.pc.in           | 2 +-
 gobject-introspection-no-export-1.0.pc.in | 2 +-
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/configure.ac b/configure.ac
index b4294c57..60506947 100644
--- a/configure.ac
+++ b/configure.ac
@@ -114,9 +114,12 @@ GIR_SUFFIX="gir-1.0"
 AC_SUBST(GIR_SUFFIX)
 AC_DEFINE_UNQUOTED(GIR_SUFFIX, "$GIR_SUFFIX", [Name of the gir directory])
 
-GIR_DIR="$EXPANDED_DATADIR/$GIR_SUFFIX"
+AC_ARG_WITH([gir-dir-prefix],
+		[AS_HELP_STRING([--with-gir-dir-prefix], [Directory prefix for gir installation])],
+		[GIR_DIR_PREFIX="$withval"], [GIR_DIR_PREFIX="$EXPANDED_DATADIR"])
+GIR_DIR="$GIR_DIR_PREFIX/$GIR_SUFFIX"
 AC_SUBST(GIR_DIR)
-AC_DEFINE_UNQUOTED(GIR_DIR, "$GIR_DIR", [Director prefix for gir installation])
+AC_DEFINE_UNQUOTED(GIR_DIR, "$GIR_DIR", [Directory prefix for gir installation])
 
 PKG_CHECK_MODULES(GLIB, [glib-2.0 >= 2.58.0])
 
diff --git a/gobject-introspection-1.0.pc.in b/gobject-introspection-1.0.pc.in
index a08b5d27..3409856c 100644
--- a/gobject-introspection-1.0.pc.in
+++ b/gobject-introspection-1.0.pc.in
@@ -10,7 +10,7 @@ g_ir_scanner=${bindir}/g-ir-scanner
 g_ir_compiler=${bindir}/g-ir-compiler@EXEEXT@
 g_ir_generate=${bindir}/g-ir-generate@EXEEXT@
 gidatadir=${datadir}/gobject-introspection-1.0
-girdir=${datadir}/gir-1.0
+girdir=@GIR_DIR@
 typelibdir=${libdir}/girepository-1.0
 
 Cflags: -I${includedir}/gobject-introspection-1.0 @FFI_PC_CFLAGS@
diff --git a/gobject-introspection-no-export-1.0.pc.in b/gobject-introspection-no-export-1.0.pc.in
index d214d22d..745aaade 100644
--- a/gobject-introspection-no-export-1.0.pc.in
+++ b/gobject-introspection-no-export-1.0.pc.in
@@ -9,7 +9,7 @@ includedir=@includedir@
 g_ir_scanner=${bindir}/g-ir-scanner
 g_ir_compiler=${bindir}/g-ir-compiler@EXEEXT@
 g_ir_generate=${bindir}/g-ir-generate@EXEEXT@
-girdir=${datadir}/gir-1.0
+girdir=@GIR_DIR@
 typelibdir=${libdir}/girepository-1.0
 
 Cflags: -I${includedir}/gobject-introspection-1.0 @FFI_PC_CFLAGS@
-- 
2.17.0