Put mem functions in SRAM

These were being placed in Flash due to a missing space

Author: will-v-pi

src/rp2_common/pico_standard_link/standard_scripts/section_default_rodata_excludes.ld

@@ -1 +1 @@
-*(EXCLUDE_FILE(*libgcc.a: *libc.a:*lib_a-mem*.o *libm.a:) .rodata*)
+*(EXCLUDE_FILE(*libgcc.a: *libc.a: *lib_a-mem*.o *libm.a:) .rodata*)

src/rp2_common/pico_standard_link/standard_scripts/section_default_text_excludes.ld

@@ -1 +1 @@
-*(EXCLUDE_FILE(*libgcc.a: *libc.a:*lib_a-mem*.o *libm.a:) .text*)
+*(EXCLUDE_FILE(*libgcc.a: *libc.a: *lib_a-mem*.o *libm.a:) .text*)