[PATCH] riscv: Fix breakage caused by linker relaxation

[Sean Anderson]

> But I wonder how U-Boot managed to work on RISC-V till today?

Hm. I think that linker relaxations may also have been disabled by
linking with -pie. When I discovered this bug, I had disabled the flag
since I was having a hard time getting my compiler to build with
--enable-shared. When recompiling with -pie and with __global_pointer
defined, the problem assembly code I noticed now uses the
two-instruction auipc/lw sequence.

	--Sean