MAINTAINERS: mailmap: update Tamir Duberstein's email address

Update Tamir Duberstein's email address to `@kernel.org`.

Signed-off-by: Tamir Duberstein <tamird@kernel.org>
Link: https://patch.msgid.link/20260126-tamird-kernel-org-v1-1-b390d329b0b9@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Author: tamird

.mailmap

@@ -797,6 +797,7 @@ Sven Eckelmann <sven@narfation.org> <sven@open-mesh.com>
 Sven Peter <sven@kernel.org> <sven@svenpeter.dev>
 Szymon Wilczek <swilczek.lx@gmail.com> <szymonwilczek@gmx.com>
 Takashi YOSHII <takashi.yoshii.zj@renesas.com>
+Tamir Duberstein <tamird@kernel.org> <tamird@gmail.com>
 Tamizh Chelvam Raja <quic_tamizhr@quicinc.com> <tamizhr@codeaurora.org>
 Taniya Das <quic_tdas@quicinc.com> <tdas@codeaurora.org>
 Tanzir Hasan <tanzhasanwork@gmail.com> <tanzirh@google.com>

MAINTAINERS

@@ -28355,7 +28355,7 @@ F:	lib/xarray.c
 F:	tools/testing/radix-tree
 
 XARRAY API [RUST]
-M:	Tamir Duberstein <tamird@gmail.com>
+M:	Tamir Duberstein <tamird@kernel.org>
 M:	Andreas Hindborg <a.hindborg@kernel.org>
 L:	rust-for-linux@vger.kernel.org
 S:	Supported