tests: cmsis_dsp: Add mps3_an547 as integration platform for FPU tests

This commit adds the `mps3_an547` board, a Cortex-M55 platform, as an
integration platform for all CMSIS-DSP FPU test cases so that the
M-Profile Vector Extension (MVE) vector function implementations are
tested in the CI.

With this change the FPU-enabled test coverage is as follows:

* mps2_an521_remote (Cortex-M33) tests FPU/DSP-enabled scalar function
  implementations.

* mps3_an547 (Cortex-M55) tests FPU/DSP-enabled MVE vector function
  implementations.

This also has a side effect of comprehensively exercising the M-Profile
Vector Extension support in the ARM architecture port, thereby ensuring
the arch-level FPU/DSP/MVE support is not broken.

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>