riscv: Remove duplicate CONFIG_PAGE_OFFSET definition

This definition is already provided by include/generated/autoconf.h,
so it does not need to be provided on the command line.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Jesse Taube <mr.bossman075@gmail.com>
Link: https://lore.kernel.org/r/20241026171441.3047904-2-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

Author: SiFiveHolland

arch/riscv/Makefile

@@ -98,7 +98,6 @@ KBUILD_AFLAGS += -march=$(riscv-march-y)
 CC_FLAGS_FPU  := -march=$(shell echo $(riscv-march-y) | sed -E 's/(rv32ima|rv64ima)([^v_]*)v?/\1\2/')
 
 KBUILD_CFLAGS += -mno-save-restore
-KBUILD_CFLAGS += -DCONFIG_PAGE_OFFSET=$(CONFIG_PAGE_OFFSET)
 
 ifeq ($(CONFIG_CMODEL_MEDLOW),y)
 	KBUILD_CFLAGS += -mcmodel=medlow