fix: Updated spellcheck list for examples/mx readme

Signed-off-by: Brandon Groth <[email protected]>

Author: BrandonGroth

.spellcheck-en-custom.txt

@@ -27,8 +27,10 @@ dequantization
 dq
 DQ
 dev
+dtype
 eval
 fms
+fmsmo
 fp
 FP
 FP8Arguments
@@ -126,6 +128,12 @@ vllm
 xs
 zp
 microxcaling
+Microscaling
+microscaling
 MX
+mx
 MXINT
+mxint
 MXFP
+mxfp
+OCP