ACPI: Remove CONFIG_GENERATE_ACPI_TABLES

As currently many systems would be barely functional without ACPI,
always generate ACPI tables if supported.

Change-Id: I372dbd03101030c904dab153552a1291f3b63518
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/4609
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@google.com>

src/arch/x86/boot/smbios.c

@@ -169,7 +169,7 @@ static int smbios_write_type0(unsigned long *current, int handle)
 		BIOS_CHARACTERISTICS_SELECTABLE_BOOT |
 		BIOS_CHARACTERISTICS_UPGRADEABLE;
 
-#if CONFIG_GENERATE_ACPI_TABLES
+#if CONFIG_HAVE_ACPI_TABLES
 	t->bios_characteristics_ext1 = BIOS_EXT1_CHARACTERISTICS_ACPI;
 #endif
 	t->bios_characteristics_ext2 = BIOS_EXT2_CHARACTERISTICS_TARGET;