pull up r23929 from trunk

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 r23929 | tlyu | 2010-04-22 21:30:48 -0400 (Thu, 22 Apr 2010) | 7 lines

 ticket: 6697
 target_version: 1.8.2
 tags: pullup

 Adapted patch from Arlene Berry to handle dlerror() returning a null
 pointer.

https://github.com/krb5/krb5/commit/83e30ba0f4d111a1b64b079ac7b8bb481c2e6b21
Commit By: tlyu
Revision: 24058
Changed Files:
U   branches/krb5-1-8/src/util/support/plugins.c