Fix the asm indent and 64-bit diretives.

Author: Kuan-Lin Chen

riscv-elf.adoc

@@ -140,8 +140,8 @@ is appeneded in .text section or put into .rodata section.
 ----
          # Get address of a symbol
          # Literal pool
-         .LCPI0:
-           .dword symbol
+.LCPI0:
+         .8byte symbol
 .Ltmp0:  auipc   a0, %pcrel_hi(.LCPI0)
          ld      a0, %pcrel_lo(.Ltmp0)(a0)
 ----
@@ -159,8 +159,8 @@ function call can reach the whole 64-bit address space.
 ----
          # Function call
          # Literal pool
-         .LCPI1:
-           .dword function
+.LCPI1:
+         .8byte function
 .Ltmp1:  auipc   a0, %pcrel_hi(.LCPI1)
          ld      a0, %pcrel_lo(.Ltmp1)(a0)
          jalr    a0