incoming

[Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>]

4 fixes, based on f313b43be461f157755a57c1156f86abe10588de:

Subject: MAINTAINERS: GDB: update e-mail address
Subject: lib/ubsan: remove null-pointer checks
Subject: mm/memory.c: check return value of ioremap_prot
Subject: zram: remove BD_CAP_SYNCHRONOUS_IO with writeback feature