configs: BPI-R2: Disable EFI Grub workaround

The EFI Grub workaround on BananaPi R2 slows down the boot process to
the point, that the watchdog will trigger a reboot before the kernel can
reset it. Fix this by disabeling the workaround.
Signed-off-by: NMatthias Brugger <mbrugger@suse.com>

configs/mt7623n_bpir2_defconfig

@@ -53,3 +53,4 @@ CONFIG_TIMER=y
 CONFIG_MTK_TIMER=y
 CONFIG_WDT_MTK=y
 CONFIG_LZMA=y
+# CONFIG_EFI_GRUB_ARM32_WORKAROUND is not set