nvida-tegra-armv7: disable fastboot (MR 4705)

We did set these variables, so it is possible to flash boot and root
partitions separately for booting with stock partition table. This
is useful for U-Boot as secondary bootloader. But it's not good for
U-Boot as primary bootloader because the resulting images have boot
and root partitions separated, so users have to create partitions
themselves and this is very confusing.

I'm suggesting to disable it in favor of doing U-Boot as primary
bootloader, this may be harder for users, but it needs to be done
only once, and this way is more fancy and is supported on more
devices than secondary bootloader.

If someone still wants to use this port with U-Boot as secondary
bootloader they can do "pmbootstrap install --split" and
"pmbootstrap export" to get 2 separate partitions to flash.

[ci:skip-build]: Already built successfully in CI.

device/community/device-nvidia-tegra-armv7/APKBUILD

@@ -6,8 +6,8 @@
 
 pkgname=device-nvidia-tegra-armv7
 pkgdesc="NVIDIA Tegra ARMv7"
-pkgver=1.1
-pkgrel=1
+pkgver=1.2
+pkgrel=0
 url="https://postmarketos.org"
 license="MIT"
 arch="armv7"
@@ -45,6 +45,6 @@ x11() {
 }
 
 sha512sums="
-e8d7c637130642a5ee5438e7f401c1870ecd1dcdca0305ab73fabf3d8548db5f054aeeacaf48abc46189bc1efdcbb5549e8afed263880e07b4932aee418041fc  deviceinfo
+b5f81887b9d78906a880d89b862dbe445129e8444fa7e41b17deaa0ff494e25455bf47f5864a219ae394b660f63061c01c00ef370e88086367a3efcbf12a4f91  deviceinfo
 8ea2030fb0c1ae181778b86dc36ed71a904dd51e1fb08114c2a124a693fc7b464cfbb14efa8422db716fb9a647afa367df094abcc14f1ccc51af8b9063de8847  modules-initfs
 "

device/community/device-nvidia-tegra-armv7/deviceinfo

@@ -16,8 +16,6 @@ deviceinfo_chassis="tablet"
 deviceinfo_external_storage="true"
 
 # Bootloader related
-deviceinfo_flash_method="fastboot-bootpart"
-deviceinfo_flash_fastboot_partition_kernel="system"
-deviceinfo_flash_fastboot_partition_system="userdata"
+deviceinfo_flash_method="none"
 deviceinfo_generate_extlinux_config="true"
 deviceinfo_kernel_cmdline="console=ttyS0,115200n8 rw gpt"