Read AA64ISAR0_EL1 to check dot product support (#16082)
### Description
Use an assembly instruction to read the `AA64ISAR0_EL1` register for dot
product support.
### Motivation and Context
The only reliable way to check for supported instruction extensions in
ARM is to
query the instruction set attribute registers. [Dot product instructions
can
be checked using bits 47:44 in the AA64ISAR0_EL1
register](https://developer.arm.com/documentation/ddi0601/2021-12/AArch64-Registers/ID-AA64ISAR0-EL1--AArch64-Instruction-Set-Attribute-Register-0?lang=en#fieldset_0-47_44).
On `qemu-aarch64` with the `a64fx` cpu which does not support the dot
product
instructions, running a quantized BERT-Large (from MLPerf) results in
`SIGILL`.
With the change, the program continues without using the dot product
instructions. Also verified that `S8S8_SDOT` kernels are invoked when
running
on hardware that supports dot product instructions.
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Co-authored-by: Skand Hurkat <skhurkat@microsoft.com>
