docs/system/arm/aspeed: Remove tacoma-bmc from the documentation

The tacoma-bmc machine has recently been removed, so let's remove
it from the documentation now, too.

Fixes: 2b1b66e01f ("arm: Remove tacoma-bmc machine")
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250124174507.27348-1-thuth@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>

docs/system/arm/aspeed.rst

@@ -1,5 +1,5 @@
-Aspeed family boards (``ast2500-evb``, ``ast2600-evb``, ``ast2700-evb``, ``bletchley-bmc``, ``fuji-bmc``, ``fby35-bmc``, ``fp5280g2-bmc``, ``g220a-bmc``, ``palmetto-bmc``, ``qcom-dc-scm-v1-bmc``, ``qcom-firework-bmc``, ``quanta-q71l-bmc``, ``rainier-bmc``, ``romulus-bmc``, ``sonorapass-bmc``, ``supermicrox11-bmc``, ``supermicrox11spi-bmc``, ``tiogapass-bmc``, ``tacoma-bmc``, ``witherspoon-bmc``, ``yosemitev2-bmc``)
-==================================================================================================================================================================================================================================================================================================================================================================================================================================
+Aspeed family boards (``ast2500-evb``, ``ast2600-evb``, ``ast2700-evb``, ``bletchley-bmc``, ``fuji-bmc``, ``fby35-bmc``, ``fp5280g2-bmc``, ``g220a-bmc``, ``palmetto-bmc``, ``qcom-dc-scm-v1-bmc``, ``qcom-firework-bmc``, ``quanta-q71l-bmc``, ``rainier-bmc``, ``romulus-bmc``, ``sonorapass-bmc``, ``supermicrox11-bmc``, ``supermicrox11spi-bmc``, ``tiogapass-bmc``, ``witherspoon-bmc``, ``yosemitev2-bmc``)
+==================================================================================================================================================================================================================================================================================================================================================================================================================
 
 The QEMU Aspeed machines model BMCs of various OpenPOWER systems and
 Aspeed evaluation boards. They are based on different releases of the