Add --with-dri-searchpath argument

* Add an extra argument to configure which allows for specifying
  different DRI driver search paths to libGL (FDO #24766)

Signed-off-by: Dan Nicholson <dbn.lists@gmail.com>

configs/autoconf.in

@@ -124,7 +124,7 @@ INSTALL_INC_DIR = $(includedir)
 DRI_DRIVER_INSTALL_DIR = @DRI_DRIVER_INSTALL_DIR@
 
 # Where libGL will look for DRI hardware drivers
-DRI_DRIVER_SEARCH_DIR = $(DRI_DRIVER_INSTALL_DIR)
+DRI_DRIVER_SEARCH_DIR = @DRI_DRIVER_SEARCH_DIR@
 
 # Xorg driver install directory (for xorg state-tracker)
 XORG_DRIVER_INSTALL_DIR = @XORG_DRIVER_INSTALL_DIR@

configure.ac

@@ -649,6 +649,13 @@ AC_ARG_WITH([dri-driverdir],
     [DRI_DRIVER_INSTALL_DIR="$withval"],
     [DRI_DRIVER_INSTALL_DIR='${libdir}/dri'])
 AC_SUBST([DRI_DRIVER_INSTALL_DIR])
+dnl Extra search path for DRI drivers
+AC_ARG_WITH([dri-searchpath],
+    [AS_HELP_STRING([--with-dri-searchpath=DIRS...],
+        [semicolon delimited DRI driver search directories @<:@${libdir}/dri@:>@])],
+    [DRI_DRIVER_SEARCH_DIR="$withval"],
+    [DRI_DRIVER_SEARCH_DIR='${DRI_DRIVER_INSTALL_DIR}'])
+AC_SUBST([DRI_DRIVER_SEARCH_DIR])
 dnl Direct rendering or just indirect rendering
 AC_ARG_ENABLE([driglx-direct],
     [AS_HELP_STRING([--disable-driglx-direct],

src/mesa/drivers/dri/Makefile

@@ -25,7 +25,7 @@ pcedit = sed \
 	-e 's,@INSTALL_LIB_DIR@,$(INSTALL_LIB_DIR),' \
 	-e 's,@INSTALL_INC_DIR@,$(INSTALL_INC_DIR),' \
 	-e 's,@VERSION@,$(MESA_MAJOR).$(MESA_MINOR).$(MESA_TINY),' \
-	-e 's,@DRI_DRIVER_DIR@,$(DRI_DRIVER_SEARCH_DIR),' \
+	-e 's,@DRI_DRIVER_DIR@,$(DRI_DRIVER_INSTALL_DIR),' \
 	-e 's,@DRI_PC_REQ_PRIV@,$(DRI_PC_REQ_PRIV),'
 
 dri.pc: dri.pc.in