There is a good document using incremental backup usage for dataguard :
Steps to perform for Rolling forward a standby database using RMAN incremental backup when primary and standby are in ASM filesystem (Doc ID 836986.1)
It was corrupted on primary side.
In that case, if you have backup of that archive log; you can restore it from backup.
If not, you can not recover that archive log and is not required to recover if you have the database backup available post the archive log generation.
However, if your concern is to sync the standby database with primary database, you can refer the note as mentioned by @meser.