update version reference in the README file

README

@@ -10,7 +10,7 @@ usage, and correctness in the sense of standards conformance and
 safety. musl is built on the principle that these goals are best
 achieved through simple code that is easy to understand and maintain.
 
-The 1.0 release series for musl features coverage for all interfaces
+The 1.1 release series for musl features coverage for all interfaces
 defined in ISO C99 and POSIX 2008 base, along with a number of
 non-standardized interfaces for compatibility with Linux, BSD, and
 glibc functionality.