u-boot-*: bump pkgrel after a-t-f upgrade (MR 3291)

Bump the remaining users of arm-trusted-firmware besides
u-boot-pinephone.

[ci:skip-build]: already built successfully in CI

device/community/u-boot-pinebookpro/APKBUILD

@@ -3,7 +3,7 @@
 # a driver for the display and supports efi loading operating systems
 pkgname=u-boot-pinebookpro
 pkgver=2020.07
-pkgrel=4
+pkgrel=5
 pkgdesc="u-boot bootloader for the rk3399"
 url="https://gitlab.denx.de/u-boot/u-boot"
 arch="aarch64"

device/community/u-boot-rockpro64/APKBUILD

@@ -4,7 +4,7 @@
 
 pkgname=u-boot-rockpro64
 pkgver=2021.07
-pkgrel=1
+pkgrel=2
 pkgdesc="u-boot bootloader for the rk3399"
 url="https://gitlab.com/pine64-org/u-boot"
 arch="aarch64"

device/testing/u-boot-rock64/APKBUILD

@@ -2,7 +2,7 @@
 
 pkgname=u-boot-rock64
 pkgver=2021.07
-pkgrel=1
+pkgrel=2
 pkgdesc="u-boot bootloader for the rk3328"
 url="https://gitlab.com/u-boot/u-boot"
 arch="aarch64"

device/testing/u-boot-sourceparts-pocketpc/APKBUILD

 # U-boot with patches to make the PinePhone boot faster and have control over the ddr clock speed
 pkgname=u-boot-sourceparts-pocketpc
 pkgver=2021.1
-pkgrel=0
+pkgrel=1
 pkgdesc="U-Boot bootloader for the Sourceparts Pocket P.C."
 url="https://source.denx.de/u-boot"
 arch="aarch64"