ARM: 8788/1: ftrace: remove old mcount support

ARM: 8788/1: ftrace: remove old mcount support

Commit cafa0010cd51 ("Raise the minimum required gcc version to 4.6")
raised the minimum GCC version to 4.6. Old mcount is only required for
GCC versions older than 4.4.0. Hence old mcount support can be dropped
too.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
[sw0312.kim: cherry-pick maline commit d3c61619568c to support llvm/clang build
 - FRAME_POINTER is required for old gcc version, and it is not really necessary for llvm/clang ]
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Change-Id: I42e61d4e9f146eeaa728b3febbf0f9782b879ee0