futex: MAINTAINERS, .mailmap: Update André's email address

Update futex entry to use my new professional email address.

Signed-off-by: André Almeida <andrealmeid@igalia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220421173254.29855-1-andrealmeid@igalia.com