Update relative links to Linux docs

This is a followup to [1].

[1] https://chromium-review.googlesource.com/c/chromium/src/+/1974901

TBR=sky

Change-Id: I442ffe121378607bdc5e1b16c081b8d66b138955
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1980900
Reviewed-by: Thomas Anderson <[email protected]>
Commit-Queue: Thomas Anderson <[email protected]>
Cr-Commit-Position: refs/heads/master@{#727226}
diff --git a/docs/android_build_instructions.md b/docs/android_build_instructions.md
index 8830485..2aeee62 100644
--- a/docs/android_build_instructions.md
+++ b/docs/android_build_instructions.md
@@ -19,7 +19,7 @@
 * You must have Git and Python installed already.
 
 Most development is done on Ubuntu. Other distros may or may not work;
-see the [Linux instructions](linux_build_instructions.md) for some suggestions.
+see the [Linux instructions](linux/build_instructions.md) for some suggestions.
 
 Building the Android client on Windows or Mac is not supported and doesn't work.