Merge pull request #304 from ericonr/readme

Fix comment in code shown in the README.

Author: veorq

README.md

@@ -150,7 +150,7 @@ int main(void)
     uint8_t *pwd = (uint8_t *)strdup(PWD);
     uint32_t pwdlen = strlen((char *)pwd);
 
-    uint32_t t_cost = 2;            // 1-pass computation
+    uint32_t t_cost = 2;            // 2-pass computation
     uint32_t m_cost = (1<<16);      // 64 mebibytes memory usage
     uint32_t parallelism = 1;       // number of threads and lanes