configure.ac: do not require the i965 driver for ANV

As of last few commits we have the two split, thus we no longer require
the i965 in order to have the ANV driver.

Even though ANV does not link against libdrm nor libdrm_intel, we still
require those as dependencies due to the headers they provide.

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

configure.ac

@@ -1786,9 +1786,8 @@ if test -n "$with_vulkan_drivers"; then
     for driver in $VULKAN_DRIVERS; do
         case "x$driver" in
         xintel)
-            if test "x$HAVE_I965_DRI" != xyes; then
-                AC_MSG_ERROR([Intel Vulkan driver requires the i965 dri driver])
-            fi
+            require_libdrm "i965"
+            PKG_CHECK_MODULES([INTEL], [libdrm >= $LIBDRM_INTEL_REQUIRED libdrm_intel >= $LIBDRM_INTEL_REQUIRED])
             HAVE_INTEL_VULKAN=yes
 
             ;;