Update stdsimd submodule

Should hopefully bring documentation for wasm intrinsics online!

diff --git a/src/stdsimd b/src/stdsimd
index fe825c93788c841ac1872e8351a62c37a5f78427..307650500de5b44dc1047dc9d15e449e09d92b57 160000 (submodule)
--- a/src/stdsimd
+++ b/src/stdsimd
@@ -1 +1 @@
-Subproject commit fe825c93788c841ac1872e8351a62c37a5f78427
+Subproject commit 307650500de5b44dc1047dc9d15e449e09d92b57