[SYCL][FPGA][NFC] Refactor of memory attribute tests (#9441)

This patch

i. updates tests for FPGA Memory Attributes below:

[[intel::numbanks()]]
[[intel::force_pow2_depth()]]
[[intel::bankwidth()]]
[[intel::max_replicates()]]
[[intel::bank_bits()]]
[[intel::private_copies()]]
[[intel::merge("mrg1", "depth")]]
[[intel::merge("mrg2", "width")]]
[[intel::fpga_register]]
[[intel::fpga_memory("MLAB")]]
[[intel::fpga_memory("BLOCK_RAM")]]
[[intel::doublepump]]
[[intel::singlepump]]
[[intel::simple_dual_port]]

ii. separates AST and diagnostics to make it easier to
read/follow-up/debug in future.

ii. removes duplicate test cases.

iii. no compiler change.

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Signed-off-by: Soumi Manna <[email protected]>

Author: smanna12