Merge version 1.6-3+rpi1 and 1.6-4 to produce 1.6-4+rpi1

diff --cc debian/changelog
index a72d8d8027a3ad99cc75aa8c9951fc54d84d5b23,97490c7be37a4c13e8941dd6f50fe0758a38132b..81e8b8b85510dbe241097fd60d55b5dce61f70b8
--- 1/debian/changelog
--- 2/debian/changelog
+++ b/debian/changelog
@@@ -1,9 -1,15 +1,22 @@@
- pocl (1.6-3+rpi1) bullseye-staging; urgency=medium
++pocl (1.6-4+rpi1) bullseye-staging; urgency=medium
 +
 +  [changes brought forward from 1.5-6+rpi1 by Peter Michael Green <plugwash@raspbian.org> at Sat, 26 Dec 2020 20:26:31 +0000]
 +  * Update symbols file for raspbian.
 +
-  -- Raspbian forward porter <root@raspbian.org>  Fri, 22 Jan 2021 12:17:44 +0000
++ -- Raspbian forward porter <root@raspbian.org>  Wed, 10 Feb 2021 16:13:40 +0000
++
+ pocl (1.6-4) unstable; urgency=medium
+ 
+   * Restore setting unroll-threshold on LLVM 9 to avoid kernel/test_rotate
+     hanging on avx512 capable cpus.  (Closes: #980626)
+   * Kill hanging tests after 30 minutes.
+   * Let dh_shlibdeps find libpocl-devices-basic.so.
+   * Do not use the embedded copy of the OpenCL headers.
+   * Build with -fvisibility-inlines-hidden.
+   * Drop hidden symbols.
+   * Bump Standards-Version to 4.5.1, no changes needed.
+ 
+  -- Andreas Beckmann <anbe@debian.org>  Wed, 03 Feb 2021 21:21:03 +0100
  
  pocl (1.6-3) unstable; urgency=medium
  

diff --cc debian/libpocl2.symbols
Simple merge