Change in coreboot[master]: soc/intel/alderlake: Add Kconfig for recommended PCIe TBT resources

[Furquan Shaikh (Code Review)]

Attention is currently required from: Tim Wawrzynczak, Subrata Banik, Patrick Rudolph, EricR Lai.
Furquan Shaikh has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/51460 )

Change subject: soc/intel/alderlake: Add Kconfig for recommended PCIe TBT resources
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Patch Set 1:

(3 comments)

File src/soc/intel/alderlake/Kconfig:

https://review.coreboot.org/c/coreboot/+/51460/comment/ded68883_e02530cd 
PS1, Line 138: ADL_MAINBOARD_SUPPORTS_PCIEXP_HOTPLUG
Just thinking some more. Should we give this a more specific name to indicate the purpose for which this configuration is being done? Something like ADL_ENABLE_USB4_PCIE_RESOURCES

https://review.coreboot.org/c/coreboot/+/51460/comment/ac525a15_6fe10f3e 
PS1, Line 142: config PCIEXP_HOTPLUG_BUSES
nit: if you use:

```
if ADL_ENABLE_USB4_PCIE_RESOURCES

config PCIEXP_HOTPLUG_BUSES
...

endif
```

you won't need to add the if conditional to each default statement.

https://review.coreboot.org/c/coreboot/+/51460/comment/82770ad8_a43f37db 
PS1, Line 143:         
Use tab instead of spaces here and in the lines below.