releasenote.md: add information about removal of CLX-SP and EMR-SP microcode

For some reason, information about removal of 06-55-06 (CLX-SP B0)
and 06-cf-01 (EMR-SP A0) microcode file is missing from microcode-20250512
release notes.  Document those properly.

* releasenote.md (microcode-20250512): Mention removal of 06-55-06
and 06-cf-01 microcode files.

Signed-off-by: Eugene Syromiatnikov <[email protected]>

Author: esyr-rh

releasenote.md

@@ -85,6 +85,13 @@
 | TWL            | N0       | 06-be-00/19 | 0000001c | 0000001d | Core i3-N305/N300, N50/N97/N100/N200, Atom x7211E/x7213E/x7425E
 | WHL-U          | V0       | 06-8e-0c/94 | 000000fc | 00000100 | Core Gen8 Mobile
 
+### Removed Platforms
+
+| Processor      | Stepping | F-M-S/PI    | Old Ver  | New Ver  | Products
+|:---------------|:---------|:------------|:---------|:---------|:---------
+| CLX-SP         | B0       | 06-55-06/bf | 04003605 |          | Xeon Scalable Gen2
+| EMR-SP         | A0       | 06-cf-01/87 | 21000291 |          | Xeon Scalable Gen5
+
 
 ## [microcode-20250211](https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files/releases/tag/microcode-20250211)