at91: switch to Linux 6.6, remove Linux 6.1 config and patches #407

Job	Run time
Build all affected Kernels / Determine Changed Files / Determine Changed Files	6s
Build all affected Kernels / Set targets	33s
Build all affected Kernels / Determine Changed Packages / Determine Changed Packages	6s
Build all affected Kernels / Check Kernel patches (at91, sam9x) / Set up build	1s
Build all affected Kernels / Build Kernel with external toolchain (at91, sama5) / Set up build at91/sama5	6s
Build all affected Kernels / Build Kernel with external toolchain (at91, sam9x) / Set up build at91/sam9x	7s
Build all affected Kernels / Build Kernel with external toolchain (at91, sama7) / Set up build at91/sama7	6s
Build all affected Kernels / Check Kernel patches (at91, sam9x) / Check Kernel patches	4m 8s
Build all affected Kernels / Build Kernel with external toolchain (at91, sama5) / Check packages for at91/sama5	3m 32s
Build all affected Kernels / Build Kernel with external toolchain (at91, sama5) / Build at91/sama5	21m 42s
Build all affected Kernels / Build Kernel with external toolchain (at91, sama7) / Build at91/sama7	25m 49s
Build all affected Kernels / Build Kernel with external toolchain (at91, sama7) / Check packages for at91/sama7	3m 5s
Build all affected Kernels / Build Kernel with external toolchain (at91, sam9x) / Check packages for at91/sam9x	3m 31s
Build all affected Kernels / Build Kernel with external toolchain (at91, sam9x) / Build at91/sam9x	20m 28s
Build all affected Kernels / Upload ccache cache to s3	0s
	1h 23m 20s

Provide feedback