Use the new scheme format in most places

The graphics subsystem still uses the old format as orbital manually
parses the fpath result.

common/src/dma.rs

@@ -22,7 +22,7 @@ const DMA_MEMTY: MemoryType = {
 
 pub(crate) fn phys_contiguous_fd() -> Result<Fd> {
     Fd::open(
-        &format!("memory:zeroed@{DMA_MEMTY}?phys_contiguous"),
+        &format!("/scheme/memory/zeroed@{DMA_MEMTY}?phys_contiguous"),
         flag::O_CLOEXEC,
         0,
     )

common/src/lib.rs

@@ -51,7 +51,7 @@ pub unsafe fn physmap(
 ) -> Result<*mut ()> {
     // TODO: arraystring?
     let path = format!(
-        "memory:physical@{}",
+        "/scheme/memory/physical@{}",
         match ty {
             MemoryType::Writeback => "wb",
             MemoryType::Uncacheable => "uc",