[linux-aarch64-chromebook] no longer boots on Asus C101PA

[divVerent]

Current kernel image is >32 MiB which seems to be the limit of the bootloader of my Chromebook (Asus C101PA).

See here where I posted my findings - including a PKGBUILD patch as a workaround that reduces kernel size but may make the kernel no longer work on other systems: viewtopic.php?f=65&t=14682

I'd suggest starting with something more generic, like, just those changes:

Disable file systems that likely nobody boots their laptop from:

```
+ scripts/config --module FAT_FS
+ scripts/config --module MSDOS_FS
+ scripts/config --module NFS_FS
+ scripts/config --module VFAT_FS
+ scripts/config --module XFS_FS
```

(XFS is technically good enough to boot Linux from but rather unlikely anyone's using that today on a laptop; NFS maybe is handy to have but not sure if anyone uses that)

Disable KVM because that's no fun on aarch64 anyway:

```
+ scripts/config --disable VIRTUALIZATION
```

Speed up kernel build time by disabling some graphics drivers that are unlikely used on anything aarch64:

```
+ scripts/config --disable DRM_AMDGPU
+ scripts/config --disable DRM_NOVEAU
+ scripts/config --disable DRM_RADEON
```

Tell the compiler to sacrifice some performance for size:

```
+ scripts/config --disable CC_OPTIMIZE_FOR_PERFORMANCE
+ scripts/config --enable CC_OPTIMIZE_FOR_SIZE
```

This subset of my changes should be rather safe for Chromebooks and should get the kernel to a working size again - for now.

Disabling whole architectures also does a lot but I can't tell which architectures other devices have (this specific Chromebook is rockchip).

Likely other related issue (also hitting a 32 MiB wall for kernel size): viewtopic.php?f=65&t=14727

[gerardr]

Agree that trimming out the 3 big x86_64 graphics drivers helps, thanks. I'm now running a 5.9.0 kernel on a GRU/Kevin chromebook, although I've also trimmed out all but the Rockchip architectures.

Again, though, as I reported in a different thread, the ARM kernel builds are several weeks behind the mainline kernel release. Hate to keep opening different "builds are behind" threads, though (I've already done one for Firefox and one for the kernel).