[offload] add support for SPIR-V kernel images

[lplewa]

The olProgramCreate entry point currently doesn't define the format of the program binary. The PluginInterface implementation currently only accepts ELF images, which won't work for backends that don't support ELF, like Level Zero. This patch adds support for loading and handling kernels in SPIR-V format.

note: test will be added after merge of #158900

[github-actions]

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