File revert1.patch of Package rpm

commit b75c4bcf82cf0e2d1e11369f5d2f9c8f47bc5e18
Author: Bernhard M. Wiedemann <bwiedemann@suse.de>
Date:   Sun Nov 10 02:52:08 2019 +0100

    Set Build Date from changelog again
    
    fa303d5ba6 had moved the code that used SOURCE_DATE_EPOCH
    to run before we do setenv here.
    
    Fixes #932

diff --git a/build/build.c b/build/build.c
index d6f418793..1bbb0ee25 100644
--- a/build/build.c
+++ b/build/build.c
@@ -254,6 +254,8 @@ static rpmRC buildSpec(rpmts ts, BTA_t buildArgs, rpmSpec spec, int what)
 		/* make sure it is in the past, so that clamping times works */
 		sdeint -= 43200;
 	    snprintf(sdestr, sizeof(sdestr), "%lli", sdeint);
+	    if(rpmExpandNumeric("%{?use_source_date_epoch_as_buildtime}"))
+	        spec->buildTime = sdeint;
 	    rpmlog(RPMLOG_NOTICE, _("setting %s=%s\n"), "SOURCE_DATE_EPOCH", sdestr);
 	    setenv("SOURCE_DATE_EPOCH", sdestr, 0);
 	    rpmtdFreeData(&td);