[U-Boot] u-boot-dm crashes early on NVIDIA Beaver, Jetson TK1

[Stephen Warren]

Simon, the latest commits in u-boot-dm/git master branch (2b64d049a061 
"power: pmic/regulator: Add basic support for TPS65910") crash on at 
least Beaver and Jetson TK1. On TK1, I added debug spew to 
lib/initcall.c, and the last function called before the crash is 
initr_serial():

> U-Boot SPL 2018.01-rc1-00620-g2b64d049a061-dirty (Dec 11 2017 - 09:50:35)
> Trying to boot from RAM
> initcall: 801602c4
> 
> 
> U-Boot 2018.01-rc1-00620-g2b64d049a061-dirty (Dec 11 2017 - 09:50:35 -0700)
> 
> initcall: 80123814
> U-Boot code: 80110000 -> 8017F6E8  BSS: -> 801C3B0C
> initcall: 80113030
> TEGRA124
> initcall: 80123dc0
> Model: NVIDIA Jetson TK1
> Board: NVIDIA Jetson TK1
> initcall: 8012394c
> DRAM:  initcall: 80111c78
> initcall: 80123ab4
> Monitor len: 000B3B0C
> Ram size: 80000000
> Ram top: 00000000
> initcall: 80123664
> initcall: 80123684
> TLB table from ffff0000 to ffff4000
> initcall: 8012367c
> initcall: 801239bc
> initcall: 801237c8
> Reserving 718k for U-Boot at: fff3c000
> initcall: 80123798
> Reserving 37896k for malloc() at: fda3a000
> initcall: 801238f8
> Reserving 88 Bytes for Board Info at: fda39fa8
> initcall: 801239c4
> initcall: 80123764
> Reserving 208 Bytes for Global Data at: fda39ed8
> initcall: 801236f8
> Reserving 30560 Bytes for FDT at: fda32778
> initcall: 801239cc
> initcall: 801239e4
> initcall: 80123b20
> initcall: 80111e0c
> initcall: 801239f8
> 
> RAM Configuration:
> Bank #0: 80000000 2 GiB
> Bank #1: 0 0 Bytes
> 
> DRAM:  2 GiB
> initcall: 801236dc
> New Stack Pointer is: fda32750
> initcall: 801238b4
> initcall: 801239d4
> initcall: 80123844
> Relocation Offset is: 7fe2c000
> Relocating to fff3c000, new gd at fda39ed8, sp at fda32750
> initcall: fff4fb64
> initcall: fff4fb6c
> initcall: 80123d54 (relocated to fff4fd54)
> initcall: 80123d1c (relocated to fff4fd1c)
> initcall: 80123d74 (relocated to fff4fd74)
> initcall: 80123ce0 (relocated to fff4fce0)
> Pre-reloc malloc() used 0x130 bytes (0 KB)
> initcall: 80123634 (relocated to fff4f634)
> initcall: 80123ccc (relocated to fff4fccc)
> initcall: 80123d7c (relocated to fff4fd7c)
> initcall: 80123cbc (relocated to fff4fcbc)
> initcall: 80123d64 (relocated to fff4fd64)
> initcall: 80123cb0 (relocated to fff4fcb0)
> initcall: 80123c9c (relocated to fff4fc9c)
> initcall: 80111d80 (relocated to fff3dd80)
> initcall: 8015670c (relocated to fff8270c)
> initcall: 8012c7f0 (relocated to fff587f0)
> initcall: 80123c8c (relocated to fff4fc8c)
> 
> U-Boot SPL 2016.09-00263-gf50db3a323b1 (Sep 23 2016 - 16:34:07)

> 80123c70 l     F .text  0000001c initr_announce
> 80123c8c l     F .text  00000010 initr_serial
> 80123c9c l     F .text  00000014 initr_dm