Add missing pragma weak declaration to lhash.h
The missing symbol caused a linker failure on solaris x86_64.
Fixes
@@ -230,6 +230,7 @@ DEFINE_LHASH_OF(OPENSSL_CSTRING);
*/
# ifdef __SUNPRO_C
# pragma weak OPENSSL_LH_new
+# pragma weak OPENSSL_LH_flush
# pragma weak OPENSSL_LH_free
# pragma weak OPENSSL_LH_insert
# pragma weak OPENSSL_LH_delete
