README.md: Fix MD030 warnings

The following warnings are generated by using markdownlint analysis:
```
README.md:101:1 MD030/list-marker-space Spaces after list markers [Expected: 1; Actual: 2]
README.md:104:1 MD030/list-marker-space Spaces after list markers [Expected: 1; Actual: 2]
```
Refer to markdown-lint [1] to fix MD030
[1]: https://github.com/updownpress/markdown-lint/blob/master/rules/030-list-marker-space.md

Signed-off-by: George Liu <liuxiwei@ieisystem.com>
Change-Id: I3cbcd5500404651ce7c98efa25504ad6dbe6284b

Author: lxwinspur

README.md

@@ -98,11 +98,11 @@ with the core:
 The libmctp code is intended to be integrated into other codebases by two
 methods:
 
-1.  as a simple library (`libmctp.{a,so}`) which can be compiled separately and
-    linked into the containing project
+1. as a simple library (`libmctp.{a,so}`) which can be compiled separately and
+   linked into the containing project
 
-2.  as a set of sources to be included into the containing project (either
-    imported, or as a git subtree/submodule)
+2. as a set of sources to be included into the containing project (either
+   imported, or as a git subtree/submodule)
 
 For (1), you can use the top-level makefile to produce `libmctp.a`.