Prepare for release of 3.0 alpha 12

Reviewed-by: NTomas Mraz <tomas@openssl.org>

CHANGES.md

@@ -21,7 +21,7 @@ OpenSSL Releases
 OpenSSL 3.0
 -----------
 
-### Changes between 1.1.1 and 3.0 [xx XXX xxxx]
+### Changes between 1.1.1 and 3.0 alpha 12 [18 Feb 2021]
 
 * The SRP APIs have been deprecated. The old APIs do not work via providers,
    and there is no EVP interface to them. Unfortunately there is no replacement

NEWS.md

@@ -18,7 +18,7 @@ OpenSSL Releases
 OpenSSL 3.0
 -----------
 
-### Major changes between OpenSSL 1.1.1 and OpenSSL 3.0 [under development]
+### Major changes between OpenSSL 1.1.1 and OpenSSL 3.0 alpha 12 [in pre-release]
 
   * Deprecated the `OCSP_REQ_CTX` type and functions.
   * Deprecated the `EC_KEY` and `EC_KEY_METHOD` types and functions.

VERSION.dat

 MAJOR=3
 MINOR=0
 PATCH=0
-PRE_RELEASE_TAG=alpha12-dev
+PRE_RELEASE_TAG=alpha12
 BUILD_METADATA=
-RELEASE_DATE=""
+RELEASE_DATE="18 Feb 2021"
 SHLIB_VERSION=3