Move to kernel 5.10

With this change, we start tracking linux 5.10. Only a couple of config
changes were necessary:

1. Explicitly include `CONFIG_IP6_NF_IPTABLES`, as it's no longer
   implicitly included.
   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=144b0a0e608690d46e9a77819249bdd8d23bdcb6

2. Move `CONFIG_EFI_VARS` to amd64 only, as it's no longer available on
   non Intel platforms. It's been replaced by `CONFIG_EFIVARS_FS` which
   is already enabled on the common config.
   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=963fabf37f6a94214a823df0a785e653cb8ad6ea

sdk_container/src/third_party/coreos-overlay/.github/workflows/kernel-releases-main.yml

@@ -13,7 +13,7 @@ jobs:
       - name: Fetch latest Kernel release
         id: fetch-latest-release
         env:
-          KV_MAIN: 5.9
+          KV_MAIN: 5.10
         run: |
           git clone --depth=1 --no-checkout https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux
           versionMain=$(git -C linux ls-remote --tags origin | cut -f2 | sed -n "/refs\/tags\/v${KV_MAIN}.[0-9]*$/s/^refs\/tags\/v//p" | sort -ruV | head -1)

sdk_container/src/third_party/coreos-overlay/sys-kernel/coreos-modules/files/amd64_defconfig-5.10

@@ -40,6 +40,7 @@ CONFIG_EDAC_I7CORE=m
 CONFIG_EDAC_I82975X=m
 CONFIG_EDAC_SBRIDGE=m
 CONFIG_EDAC_X38=m
+CONFIG_EFI_VARS=m
 CONFIG_FB_HYPERV=m
 CONFIG_FB_VESA=y
 CONFIG_FCOE_FNIC=m

sdk_container/src/third_party/coreos-overlay/sys-kernel/coreos-modules/files/commonconfig-5.10

@@ -169,7 +169,6 @@ CONFIG_EDAC=m
 CONFIG_EFI=y
 CONFIG_EFIVAR_FS=y
 CONFIG_EFI_STUB=y
-CONFIG_EFI_VARS=m
 # CONFIG_ENABLE_WARN_DEPRECATED is not set
 CONFIG_ENA_ETHERNET=m
 CONFIG_ENCLOSURE_SERVICES=m
@@ -272,6 +271,7 @@ CONFIG_INPUT_MOUSEDEV=m
 # CONFIG_INPUT_MOUSEDEV_PSAUX is not set
 CONFIG_IOSCHED_BFQ=y
 CONFIG_IO_STRICT_DEVMEM=y
+CONFIG_IP6_NF_IPTABLES=m
 CONFIG_IP6_NF_FILTER=m
 CONFIG_IP6_NF_MANGLE=m
 CONFIG_IP6_NF_MATCH_AH=m

sdk_container/src/third_party/coreos-overlay/sys-kernel/coreos-sources/Manifest

@@ -1,2 +1,2 @@
-DIST linux-5.9.tar.xz 115507140 BLAKE2B e8d11472d63a9f8409ca12a2e8c97c6963a3d4516b5a398b627d6ece565584526f9b5a1377a2fa4bd184c09c7db94c987428bc5d52df0c788464a67e9e8d6dcb SHA512 d3d92ce4246bad74c9a784212f160d98449b1e8793970c2c308276568d852b8effe0528686bdb87d55d691f09a826abf7938d69bdd4759ce65ddd5c05ffe4eca
-DIST patch-5.9.14.xz 637952 BLAKE2B fc328fa4c15423668b250b6516b8ea1a543d1b0fa4b55a493bd2c88225e6a7b391cd3fe6c40c3468937741d98b160c4e1b7f6883c21d3a352e4f4258b07a166e SHA512 d63fc8ca45e78ed5e13d1092d1a3707cbff0cd2f13a066255f7cf707dbffd96480c33ac52b73dc101ce4a0e2b7604c6dd5db1e2f5f6bfd1fcd17876de30ebb9a
+DIST linux-5.10.tar.xz 116606704 BLAKE2B b923d7b66309224f42f35f8a5fa219421b0a9362d2adacdadd8d96251f61f7230878ea297a269a7f3b3c56830f0b177e068691e1d7f88501a05653b0a13274d1 SHA512 95bc137d0cf9148da6a9d1f1a878698dc27b40f68e22c597544010a6c591ce1b256f083489d3ff45ff77753289b535135590194d88ef9f007d0ddab3d74de70e
+DIST patch-5.10.4.xz 199992 BLAKE2B b79c50e4f52dfef44ddf137e1f69c47b0172771543afe6598cbcc263330634414d992e32e2be33e7682bc4c2f229a6f7a08a5ff02ebbda682a11cb70dbc01b56 SHA512 893733c9b9290f7a91bfb31ca9baa762a6460665b59efad6ee194b67807ae3990cf44464a32ea4a7e9620b58d7810ff15a30a7d92f0bf1b14cff3b5730fce49c

sdk_container/src/third_party/coreos-overlay/sys-kernel/coreos-sources/coreos-sources-5.10.4.ebuild

@@ -8,7 +8,7 @@ ETYPE="sources"
 # Final releases should be versioned L.M.N, even for N == 0
 
 # Only needed for RCs
-K_BASE_VER="5.9"
+K_BASE_VER="5.10"
 
 inherit kernel-2
 EXTRAVERSION="-flatcar"