[M] Change in coreboot[master]: soc/amd/common/block/lpc/spi_dma: Leverage CBFS_CACHE when using SPI DMA

[Tim Van Patten (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Martin Roth, Fred Reitberger, Karthik Ramasubramanian, Felix Held.

Tim Van Patten has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74334 )

Change subject: soc/amd/common/block/lpc/spi_dma: Leverage CBFS_CACHE when using SPI DMA
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Patch Set 4:

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/74334/comment/9f34cac5_2952018d 
PS4, Line 13: de-compression
typo: de-compressed

File src/soc/amd/common/block/lpc/spi_dma.c:

https://review.coreboot.org/c/coreboot/+/74334/comment/c4e2c1f1_e9e64b05 
PS4, Line 218: 	if (!CONFIG_CBFS_CACHE_SIZE)
I suggest updating this to:

```
    // Assume the destination returned by `mem_pool_alloc()` is aligned.
    if (!CONFIG_CBFS_CACHE_SIZE || !can_use_dma(LPC_ROM_DMA_MIN_ALIGNMENT, offset, size))
```

Otherwise, `spi_dma_readat_mmap()` (via `spi_dma_readat()`, called later) will perform an extra copy into the cache, which we can avoid.

https://review.coreboot.org/c/coreboot/+/74334/comment/296755da_5c5df2a3 
PS4, Line 223: 		printk(BIOS_INFO, "%s: Could not allocate from memory pool\n", __func__);
Please log `size` here also, so we know how much we're trying to allocate and whether it even has a chance to succeed or not.