jemalloc: pass `--enable-valgrind` when valgrind is enabled
jemalloc: pass `--enable-valgrind` when valgrind is enabled

aidancully/rust,GBGamer/rust,aidancully/rust,GBGamer/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,GBGamer/rust,graydon/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,graydon/rust,GBGamer/rust,GBGamer/rust,aidancully/rust,graydon/rust,graydon/rust,aidancully/rust