Correct the floating+dsp options for Cortex-M processors
Correct the floating+dsp options for Cortex-M processors

As per the IAR Development guide, below options for CPU are valid

1. Cortex-M33
2. Cortex-M33.no_dsp (core without integer DSP extension)
3. Cortex-M33.fp (floating-point unit with support for single precision)
4. Cortex-M33.no_se (core without support for TrustZone)
5. Cortex-M4
6. Cortex-M4F
7. Cortex-M7
8. Cortex-M7.fp.dp (floating-point unit with support for double precision)
9. Cortex-M7.fp.sp (floating-point unit with support for single precision)

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