stm32cube: stm32h7rsxx: update readme file

- remove closed bugzilla ticket.

Signed-off-by: Fabrice DJIATSA <fabrice.djiatsa-ext@st.com>

Author: djiatsaf-st

stm32cube/stm32h7rsxx/README

@@ -44,10 +44,6 @@ Patch List:
     -Added stm32cube/stm32h7rsxx/drivers/include/stm32_assert.h
     -Removed unused stm32cube/stm32h7rsxx/drivers/include/stm32_assert_template.h
 
-   *configure the SMPS on the stm32h7s7 so that power config is possible
-    on the stm32h7s78 disco kit
-    -internal ticket 175303
-
    *Fix to remove PAGESIZE definition which conflicts with POSIX
     Impacted files:
      drivers/include/Legacy/stm32_hal_legacy.h