Remove unnecessary ENV_RAMSTAGE guard

TEST=Able to build coreboot for CML.

Change-Id: Ic0f473e04ffc1de50dee871af52eacf0b328b376
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32764
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/arch/x86/include/arch/acpi.h

@@ -838,14 +838,12 @@ void acpi_create_ivrs(acpi_ivrs_t *ivrs,
 		      unsigned long (*acpi_fill_ivrs)(acpi_ivrs_t *ivrs_struct,
 		      unsigned long current));
 
-#if ENV_RAMSTAGE && !defined(__SIMPLE_DEVICE__)
 void acpi_create_hpet(acpi_hpet_t *hpet);
 unsigned long acpi_write_hpet(struct device *device, unsigned long start,
 			      acpi_rsdp_t *rsdp);
 
 /* cpu/intel/speedstep/acpi.c */
 void generate_cpu_entries(struct device *device);
-#endif
 
 void acpi_create_mcfg(acpi_mcfg_t *mcfg);