README: fix markdown list nesting

README.md

diff --git a/README.md b/README.md
index e162c59..7efb91c 100644
--- a/README.md
+++ b/README.md
@@ -8,9 +8,9 @@
  2. 2KB of SRAM
  3. An SPI flash memory controller with 1024kb of instruction/data cache
  3. A Wishbone interconnect/fabric containing:
-   1. An SPI controller
-   2. A GPIO controller
-   3. A simple timer
+     1. An SPI controller
+     2. A GPIO controller
+     3. A simple timer
 
 Notably absent are: an interrupt system and a debug interface.