[dev.boringcrypto] misc/boring: add new releases to RELEASES file

Change-Id: I1f87576622e2286ae9bc8cd19745d80d7860b293
Reviewed-on: https://go-review.googlesource.com/c/go/+/312295
Trust: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: Katie Hockman <katie@golang.org>

misc/boring/RELEASES

@@ -131,3 +131,7 @@ go1.15.10b5 229a39e34717 linux-amd64 https://go-boringcrypto.storage.googleapis.
 go1.15.10b5 229a39e34717 src https://go-boringcrypto.storage.googleapis.com/go1.15.10b5.src.tar.gz adbaff96b2392a9ab5a20d15fec959983861ec6e554c3c9cd14aec586a0928b3
 go1.16.2b7 6d5f0ffc93e5 linux-amd64 https://go-boringcrypto.storage.googleapis.com/go1.16.2b7.linux-amd64.tar.gz 2871d90630706eba9d3bd2838ec1c0a367c78c2c4f40e74ed75c294e2c5aa358
 go1.16.2b7 6d5f0ffc93e5 src https://go-boringcrypto.storage.googleapis.com/go1.16.2b7.src.tar.gz 8991c28e30bdd9b34076c2871ab69aac7f306dba08d202aa7301f3adb54ad9f3
+go1.15.11b5 be25192f119e linux-amd64 https://go-boringcrypto.storage.googleapis.com/go1.15.11b5.linux-amd64.tar.gz c5aa34a83631b3736bc1ab37027bc4fc22eca2353035586a6255be7e29251f43
+go1.15.11b5 be25192f119e src https://go-boringcrypto.storage.googleapis.com/go1.15.11b5.src.tar.gz 05408824d64ac8ebb6c1d895017e605d45a2c4ebee28995136fe12f4833652d2
+go1.16.3b7 fcee6b930a01 linux-amd64 https://go-boringcrypto.storage.googleapis.com/go1.16.3b7.linux-amd64.tar.gz afe15efce3c1fecc60994d7ba0d41daaa029fa5810c98737121dde7b38a5e2ac
+go1.16.3b7 fcee6b930a01 src https://go-boringcrypto.storage.googleapis.com/go1.16.3b7.src.tar.gz 5c86175ed86e6ae3826eb827cc51bdda770f22ffaf3258b11135a268153b5057