doc: fix some typos in Linux guide

[ upstream commit 5b2b0bd ]

The display was not proper due to the missing space. Changed
arm64 to aarch64.

Fixes: 2eb7c52 ("doc: clarify IOMMU disabling for uio_pci_generic")

Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>

doc/guides/linux_gsg/linux_drivers.rst

@@ -52,8 +52,8 @@ be loaded as shown below:
 
    If the devices used for DPDK are bound to the ``uio_pci_generic`` kernel module,
    please make sure that the IOMMU is disabled or passthrough. One can add
-   ``intel_iommu=off`` or ``amd_iommu=off`` or ``intel_iommu=on iommu=pt``in GRUB
-   command line on x86_64 systems, or add ``iommu.passthrough=1`` on arm64 system.
+   ``intel_iommu=off`` or ``amd_iommu=off`` or ``intel_iommu=on iommu=pt`` in GRUB
+   command line on x86_64 systems, or add ``iommu.passthrough=1`` on aarch64 system.
 
 Since DPDK release 1.7 onward provides VFIO support, use of UIO is optional
 for platforms that support using VFIO.