crypt32: Remove an unneeded assignment.

dlls/crypt32/chain.c

diff --git a/dlls/crypt32/chain.c b/dlls/crypt32/chain.c
index e5ad7dc..0d1a2f0 100644
--- a/dlls/crypt32/chain.c
+++ b/dlls/crypt32/chain.c
@@ -619,7 +619,7 @@
         *trustErrorStatus |= CERT_TRUST_INVALID_NAME_CONSTRAINTS;
     else if (!name)
         ; /* no match */
-    else if ((at = strchrW(constraint, '@')))
+    else if (strchrW(constraint, '@'))
         match = !lstrcmpiW(constraint, name);
     else
     {