site/risc-v: Cache common variables to build libIDL

These variables force runtime tests during configure
they are already cached for other architectures

(From OE-Core rev: 7a0e456d9dcfe9d9d9a0dbd24a6083c8d40516ff)

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/site/riscv32-linux

@@ -1,3 +1,8 @@
+# general
+ac_cv_alignof_guint32=4
+ac_cv_alignof_guint64=8
+ac_cv_alignof_unsigned_long=4
+
 # glib-2.0
 glib_cv_stack_grows=${glib_cv_stack_grows=no}
 glib_cv_uscore=${glib_cv_uscore=no}

meta/site/riscv64-linux

@@ -1,3 +1,8 @@
+# general
+ac_cv_alignof_guint32=4
+ac_cv_alignof_guint64=8
+ac_cv_alignof_unsigned_long=8
+
 # glib-2.0
 glib_cv_stack_grows=${glib_cv_stack_grows=no}
 glib_cv_uscore=${glib_cv_uscore=no}