[riscv64] Build linux-libc-dev (Closes: #886440).

Thanks to Manuel A. Fernandez Montecelo.

debian/changelog

@@ -1,5 +1,6 @@
 linux (4.17.6-2) UNRELEASED; urgency=medium
 
+  [ Ben Hutchings ]
   * [armhf] drm/sun4i: Ignore ABI changes (fixes FTBFS)
   * debian/control: Fix arch/profile qualifications for libelf-dev
     build-dependency
@@ -14,6 +15,10 @@ linux (4.17.6-2) UNRELEASED; urgency=medium
     - [arm64,powerpc,x86] Add build salt to the vDSO
     - Set BUILD_SALT equal to the release string
 
+  [ Vagrant Cascadian ]
+  * [riscv64] Build linux-libc-dev (Closes: #886440).
+    Thanks to Manuel A. Fernandez Montecelo.
+
  -- Ben Hutchings <ben@decadent.org.uk>  Thu, 12 Jul 2018 15:16:15 +0100
 
 linux (4.17.6-1) unstable; urgency=medium

debian/config/defines

@@ -97,6 +97,7 @@ arches:
  powerpcspe
  ppc64
  ppc64el
+ riscv64
  s390
  s390x
  sh3

debian/config/riscv64/defines

@@ -0,0 +1,4 @@
+[base]
+kernel-arch: riscv
+featuresets:
+# empty; just building headers yet