arm: armv7m: remove un-necessary If then instruction

With gas option -mimplicit-it=always, IT block is inserted by the assembler
for thumb2.

Signed-off-by: Vikas Manocha <vikas.manocha@st.com>

arch/arm/lib/crt0.S

@@ -139,9 +139,6 @@ here:
 	mov	r2, #0x00000000		/* prepare zero to clear BSS */
 
 clbss_l:cmp	r0, r1			/* while not at end of BSS */
-#if defined(CONFIG_CPU_V7M)
-	itt	lo
-#endif
 	strlo	r2, [r0]		/* clear 32-bit BSS word */
 	addlo	r0, r0, #4		/* move to next */
 	blo	clbss_l