x86: acpi: Clean up table header revisions

The comment of initializing table header revision says:

    /* ACPI 1.0/2.0: 1, ACPI 3.0: 2, ACPI 4.0: 3 */

which might mislead it may increase per ACPI spec revision.
However this is not the case. It's actually a fixed number
as defined in ACPI spec, and in the laest ACPI spec 6.1,
some table header revisions are still 1. Clean these up.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

arch/x86/include/asm/acpi_table.h

@@ -31,12 +31,6 @@ struct acpi_rsdp {
 	u8 reserved[3];
 };
 
-#define ACPI_REV_ACPI_1_0	1
-#define ACPI_REV_ACPI_2_0	1
-#define ACPI_REV_ACPI_3_0	2
-#define ACPI_REV_ACPI_4_0	3
-#define ACPI_REV_ACPI_5_0	5
-
 /* Generic ACPI header, provided by (almost) all tables */
 struct acpi_table_header {
 	char signature[4];	/* ACPI signature (4 ASCII characters) */

arch/x86/lib/acpi_table.c

@@ -67,9 +67,7 @@ static void acpi_write_rsdt(struct acpi_rsdt *rsdt)
 	/* Fill out header fields */
 	acpi_fill_header(header, "RSDT");
 	header->length = sizeof(struct acpi_rsdt);
-
-	/* ACPI 1.0/2.0: 1, ACPI 3.0: 2, ACPI 4.0: 3 */
-	header->revision = ACPI_REV_ACPI_2_0;
+	header->revision = 1;
 
 	/* Entries are filled in later, we come with an empty set */
 
@@ -85,9 +83,7 @@ static void acpi_write_xsdt(struct acpi_xsdt *xsdt)
 	/* Fill out header fields */
 	acpi_fill_header(header, "XSDT");
 	header->length = sizeof(struct acpi_xsdt);
-
-	/* ACPI 1.0/2.0: 1, ACPI 3.0: 2, ACPI 4.0: 3 */
-	header->revision = ACPI_REV_ACPI_2_0;
+	header->revision = 1;
 
 	/* Entries are filled in later, we come with an empty set */
 
@@ -248,9 +244,7 @@ static void acpi_create_madt(struct acpi_madt *madt)
 	/* Fill out header fields */
 	acpi_fill_header(header, "APIC");
 	header->length = sizeof(struct acpi_madt);
-
-	/* ACPI 1.0/2.0: 1, ACPI 3.0: 2, ACPI 4.0: 3 */
-	header->revision = ACPI_REV_ACPI_2_0;
+	header->revision = 4;
 
 	madt->lapic_addr = LAPIC_DEFAULT_BASE;
 	madt->flags = ACPI_MADT_PCAT_COMPAT;
@@ -296,9 +290,7 @@ static void acpi_create_mcfg(struct acpi_mcfg *mcfg)
 	/* Fill out header fields */
 	acpi_fill_header(header, "MCFG");
 	header->length = sizeof(struct acpi_mcfg);
-
-	/* ACPI 1.0/2.0: 1, ACPI 3.0: 2, ACPI 4.0: 3 */
-	header->revision = ACPI_REV_ACPI_2_0;
+	header->revision = 1;
 
 	current = acpi_fill_mcfg(current);