ARC: show_regs: reduce lines of output

Before
------

| CPU: 1 PID: 29061 Comm: tst-dynarray-at Not tainted 5.6.0-rc1-00002-g941fcc018ca6-dirty #12
|
| [ECR   ]: 0x00090000 =>
| [EFA   ]: 0x00000000
| [ERET  ]: 0x2004aa6c
|     @off 0x2aa6c in [/lib/libc-2.31.9000.so]
      VMA: 0x20020000 to 0x20122000
| [STAT32]: 0x80080a82 [IE U     ]
| BTA: 0x2004aa18 SP: 0x5ffff8a8  FP: 0x5ffff8fc
| LPS: 0x2008788e LPE: 0x20087896 LPC: 0x00000000
| r00: 0x00000000 r01: 0x5ffff8a8 r02: 0x00000000
| r03: 0x00000008 r04: 0xffffffff r05: 0x00000000
| r06: 0x00000000 r07: 0x00000000 r08: 0x00000087
| r09: 0x00000000 r10: 0x2010691c r11: 0x00000020
| r12: 0x2003b214 r13: 0x5ffff8a8 r14: 0x20126e68
| r15: 0x2001f26c r16: 0x2012a000 r17: 0x00000001
| r18: 0x5ffff8fc r19: 0x00000000 r20: 0x5ffff948
| r21: 0x00000001 r22: 0xffffffff r23: 0x5fffff8c
| r24: 0x4008c2a8 r25: 0x2001f6e0

After
-----

| CPU: 1 PID: 29061 Comm: tst-dynarray-at Not tainted 5.6.0-rc1-00002-g941fcc018ca6-dirty #12
|   @off 0x2aa6c in [/lib/libc-2.31.9000.so]  VMA: 0x20020000 to 0x20122000
| ECR: 0x00090000 EFA: 0x00000000 ERET: 0x2004aa6c
| STAT32: 0x80080a82 [IE U     ]  BTA: 0x2004aa18
| BLK: 0x2003b214  SP: 0x5ffff8a8  FP: 0x5ffff8fc
| LPS: 0x2008788e LPE: 0x20087896 LPC: 0x00000000
| r00: 0x00000000 r01: 0x5ffff8a8 r02: 0x00000000
| r03: 0x00000008 r04: 0xffffffff r05: 0x00000000
| r06: 0x00000000 r07: 0x00000000 r08: 0x00000087
| r09: 0x00000000 r10: 0x2010691c r11: 0x00000020
| r12: 0x2003b214 r13: 0x5ffff8a8 r14: 0x20126e68
| r15: 0x2001f26c r16: 0x2012a000 r17: 0x00000001
| r18: 0x5ffff8fc r19: 0x00000000 r20: 0x5ffff948
| r21: 0x00000001 r22: 0xffffffff r23: 0x5fffff8c
| r24: 0x4008c2a8 r25: 0x2001f6e0 BTA: 0x2004aa18

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>