Fix reversed meaning of error codes

The meaning of the X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY and X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT error codes were still reversed in the X509_STORE_CTX_get_error function documentation.
This used to be the problem also in the verify application documentation, but was fixed on 2010-02-23 in 7d3d1788.
Reviewed-by: NShane Lontis <shane.lontis@oracle.com>
Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9529)

(cherry picked from commit 6d5aa88d74b67b1bc108e121dea687a4ca67e329)

doc/man3/X509_STORE_CTX_get_error.pod

@@ -101,8 +101,8 @@ the operation was successful.
 
 =item B<X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT: unable to get issuer certificate>
 
-the issuer certificate could not be found: this occurs if the issuer certificate
-of an untrusted certificate cannot be found.
+the issuer certificate of a locally looked up certificate could not be found.
+This normally means the list of trusted certificates is not complete.
 
 =item B<X509_V_ERR_UNABLE_TO_GET_CRL: unable to get certificate CRL>
 
@@ -180,8 +180,8 @@ the root could not be found locally.
 
 =item B<X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY: unable to get local issuer certificate>
 
-the issuer certificate of a locally looked up certificate could not be found.
-This normally means the list of trusted certificates is not complete.
+the issuer certificate could not be found: this occurs if the issuer certificate
+of an untrusted certificate cannot be found.
 
 =item B<X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE: unable to verify the first certificate>