boards: lilygo: ttgo_tbeam: remove not-needed kconfig opts

The boards defconfig enabled CONFIG_(MFD|REGULATOR), which are not
stricly needed if the corresponding node is not enabled in the device
tree. These options also enable many drivers, which are problematic on
the mcuboot bootloader target. By moving them to the Kconfig, we can
make them depend on !MCUBOOT which restores the sysboot target.

Signed-off-by: Felix Moessbauer <felix.moessbauer@gmail.com>

boards/lilygo/ttgo_tbeam/Kconfig

@@ -8,3 +8,9 @@ config HEAP_MEM_POOL_ADD_SIZE_BOARD
 
 config GNSS_INIT_PRIORITY
 	default 87
+
+config MFD
+	default y if !MCUBOOT
+
+config REGULATOR
+	default y if !MCUBOOT

boards/lilygo/ttgo_tbeam/ttgo_tbeam_esp32_procpu_defconfig

@@ -6,5 +6,3 @@ CONFIG_UART_CONSOLE=y
 CONFIG_UART_INTERRUPT_DRIVEN=y
 
 CONFIG_GPIO=y
-CONFIG_MFD=y
-CONFIG_REGULATOR=y