x86: Drop RAMTOP Kconfig

We don't need this in U-Boot since we calculate it based on available memory.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 7d007bb..e992e64 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -47,10 +47,6 @@
 	hex
 	default 0x100000
 
-config RAMTOP
-	hex
-	default 0x200000
-
 config XIP_ROM_SIZE
 	hex
 	default ROM_SIZE
diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
index 5f05a48..dcc995d 100644
--- a/arch/x86/include/asm/mtrr.h
+++ b/arch/x86/include/asm/mtrr.h
@@ -100,10 +100,6 @@
 
 #endif
 
-#if !defined(CONFIG_RAMTOP)
-# error "CONFIG_RAMTOP not defined"
-#endif
-
 #if ((CONFIG_XIP_ROM_SIZE & (CONFIG_XIP_ROM_SIZE - 1)) != 0)
 # error "CONFIG_XIP_ROM_SIZE is not a power of 2"
 #endif
@@ -114,8 +110,4 @@
 
 #define CACHE_ROM_BASE	(((1 << 20) - (CONFIG_CACHE_ROM_SIZE >> 12)) << 12)
 
-#if (CONFIG_RAMTOP & (CONFIG_RAMTOP - 1)) != 0
-# error "CONFIG_RAMTOP must be a power of 2"
-#endif
-
 #endif