Rename Intel to x86-64 to avoid confusion

Much of our documentation on how to build Chromium/etc. says that an
"Intel" machine is needed. This has never been true. What is needed is
an x86-64 machine - it could be Intel, AMD, or a custom processor
with transistors created using very small tweezers.

This change simply replaces [64-bit] Intel with x86-64 in seven places
in our documentation.

Change-Id: If1d1ef045b4de85d8f12e1c2051c332ac2890624
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5627158
Commit-Queue: Bruce Dawson <[email protected]>
Reviewed-by: Dave Tapuska <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1314189}
diff --git a/docs/windows_build_instructions.md b/docs/windows_build_instructions.md
index 3a151a4..fc45b7d 100644
--- a/docs/windows_build_instructions.md
+++ b/docs/windows_build_instructions.md
@@ -12,7 +12,7 @@
 
 ## System requirements
 
-* A 64-bit Intel machine with at least 8GB of RAM. More than 16GB is highly
+* An x86-64 machine with at least 8GB of RAM. More than 16GB is highly
   recommended.
 * At least 100GB of free disk space on an NTFS-formatted hard drive. FAT32
   will not work, as some of the Git packfiles are larger than 4GB.