Remove rust-analyzer git submodule

Author: fasterthanlime

.gitmodules

@@ -38,9 +38,6 @@
 [submodule "src/doc/embedded-book"]
 	path = src/doc/embedded-book
 	url = https://github.com/rust-embedded/book.git
-[submodule "src/tools/rust-analyzer"]
-	path = src/tools/rust-analyzer
-	url = https://github.com/rust-analyzer/rust-analyzer.git
 [submodule "library/backtrace"]
 	path = library/backtrace
 	url = https://github.com/rust-lang/backtrace-rs.git