cmake: iar: remove linker optimization workaround

Remove linker optimization workaround for IAR linker as the new
inheritance scheme allows empty linker values.

Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>

Author: tejlmand

cmake/linker/iar/linker_flags.cmake

@@ -4,24 +4,12 @@
 
 # Override the default CMake's IAR ILINK linker signature
 
-# The default behaviour of these new optimization flags for the linker
-# is to use the compiler optimization flags if no flags are set.
-# This does not work for IAR tools as there are no optimization flags
-# for the linker, and leaving the property empty causes it to be
-# filled with the compiler flags.
-# This workaround adds extra info to the map file only so should not
-# affect the generated code
-# To have this working properly, either the automatic use of compiler
-# flags must be removed, or we add some kind of dummy do nothing
-# command line option to the linker.
-# Either way, as this is causing an error right now, we use this
-# temporary workaround.
-
-set_property(TARGET linker PROPERTY no_optimization --entry_list_in_address_order)
-set_property(TARGET linker PROPERTY optimization_debug --entry_list_in_address_order)
-set_property(TARGET linker PROPERTY optimization_speed --entry_list_in_address_order)
-set_property(TARGET linker PROPERTY optimization_size --entry_list_in_address_order)
-set_property(TARGET linker PROPERTY optimization_size_aggressive --entry_list_in_address_order)
+# IAR linker doesn't support dedicated linker optimization flags.
+set_property(TARGET linker PROPERTY no_optimization "")
+set_property(TARGET linker PROPERTY optimization_debug "")
+set_property(TARGET linker PROPERTY optimization_speed "")
+set_property(TARGET linker PROPERTY optimization_size "")
+set_property(TARGET linker PROPERTY optimization_size_aggressive "")
 
 set_linker_property(TARGET linker PROPERTY undefined "--keep=")