Revert "arch: Replace ar and nm with gcc-ar and gcc-nm"

This reverts commit b05737d78f.

Because it broke clang-based builds.

boards/arm/imxrt/teensy-4.x/scripts/Make.defs

@@ -34,6 +34,16 @@ else
   ARCHSCRIPT = -T$(BOARD_DIR)$(DELIM)scripts$(DELIM)$(LDSCRIPT)
 endif
 
+CC = $(CROSSDEV)gcc
+CXX = $(CROSSDEV)g++
+CPP = $(CROSSDEV)gcc -E
+LD = $(CROSSDEV)gcc
+STRIP = $(CROSSDEV)strip --strip-unneeded
+AR = $(CROSSDEV)ar rcs
+NM = $(CROSSDEV)nm
+OBJCOPY = $(CROSSDEV)objcopy
+OBJDUMP = $(CROSSDEV)objdump
+
 ARCHCCVERSION = ${shell $(CC) -v 2>&1 | sed -n '/^gcc version/p' | sed -e 's/^gcc version \([0-9\.]\)/\1/g' -e 's/[-\ ].*//g' -e '1q'}
 ARCHCCMAJOR = ${shell echo $(ARCHCCVERSION) | cut -d'.' -f1}